RISC-V: Adapt VLS init tests

Realize that init tests are wrong by my previous mistakes.
Fix them and committed.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/vls/def.h: Fix init test.
	* gcc.target/riscv/rvv/autovec/vls/init-1.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-2.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-3.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-4.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-5.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-6.c: Ditto.
	* gcc.target/riscv/rvv/autovec/vls/init-7.c: Ditto.