RISC-V: Rename vx_vadd-* testcase to vx-* for all vx combine [NFC]

RISC-V: Rename vx_vadd-* testcase to vx-* for all vx combine [NFC]

We would like to arrange all vx combine asm check test into
one file for better management.  Thus, rename vx_vadd-* to
vx-*.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-1-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-1-u8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-2-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-2-u8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-3-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-3-u8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-4-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-4-u8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-5-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-5-u8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-i16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-i16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-i32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-i32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-i64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-i64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-i8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-i8.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-u16.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-u16.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-u32.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-u32.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-u64.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-u64.c: ...here.
	* gcc.target/riscv/rvv/autovec/vx_vf/vx_vadd-6-u8.c: Move to...
	* gcc.target/riscv/rvv/autovec/vx_vf/vx-6-u8.c: ...here.

Signed-off-by: Pan Li <pan2.li@intel.com>