RISC-V: Add COND_LEN_FNMA/COND_LEN_FMS/COND_LEN_FNMS testcases

RISC-V: Add COND_LEN_FNMA/COND_LEN_FMS/COND_LEN_FNMS testcases

This patch is depending on middle-end patch:
https://gcc.gnu.org/pipermail/gcc-patches/2023-August/627621.html

We already had COND_LEN_FNMA/COND_LEN_FMS/COND_FNMS patterns.

Remove TARGET_PREFERRED_ELSE_VALUE since it forbid the COND_LEN_FMS/COND_LEN_FNMS STMT fold.

gcc/ChangeLog:

	* config/riscv/riscv.cc (riscv_preferred_else_value): Remove it since
	it forbid COND_LEN_FMS/COND_LEN_FNMS STMT fold.
	(TARGET_PREFERRED_ELSE_VALUE): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/binop/vadd-rv32gcv-nofm.c: Adapt test.
	* gcc.target/riscv/rvv/autovec/binop/vadd-rv64gcv-nofm.c: Ditto.
	* gcc.target/riscv/rvv/autovec/cond/cond_fadd-1.c: Ditto.
	* gcc.target/riscv/rvv/autovec/cond/cond_fadd-2.c: Ditto.
	* gcc.target/riscv/rvv/autovec/cond/cond_fadd-3.c: Ditto.
	* gcc.target/riscv/rvv/autovec/cond/cond_fadd-4.c: Ditto.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-1.c: Ditto.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-3.c: Ditto.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-10.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-11.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-12.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-4.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-5.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-6.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-7.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-8.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm-9.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-10.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-11.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-12.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-4.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-5.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-6.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-7.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-8.c: New test.
	* gcc.target/riscv/rvv/autovec/ternop/ternop_nofm_run-9.c: New test.