Fix minor testsuite scan failures for RISC-V

Fix minor testsuite scan failures for RISC-V

This fixes minor testsuite fallout after some of Jan's recent changes, nothing
of real significance, just minor changes in codegen causing scan tests to fail.
It's mostly an -O1/-Og problem and we can just skip the tests for those.

gcc/testsuite
	* gcc.target/riscv/rvv/vsetvl/imm_switch-6.c: Skip scan-asm test for -O1 too.
	* gcc.target/riscv/rvv/vsetvl/imm_switch-7.c: Likewise.
	* gcc.target/riscv/shrink-wrap-1.c: Likewise.  Skip for -Og as well.
	* gcc.target/riscv/xandes/xandesperf-1.c: Adjust expected output.