Don't force_reg operands[3] when it's not const0_rtx.

Don't force_reg operands[3] when it's not const0_rtx.

It fix the regression by

a51f2fc0d80869ab079a93cc3858f24a1fd28237 is the first bad commit
commit a51f2fc0d80869ab079a93cc3858f24a1fd28237
Author: liuhongt <hongtao.liu@intel.com>
Date:   Wed Sep 4 15:39:17 2024 +0800

    Handle const0_operand for *avx2_pcmp<mode>3_1.

caused

FAIL: gcc.target/i386/pr59539-1.c scan-assembler-times vmovdqu|vmovups 1

To reproduce:

$ cd {build_dir}/gcc && make check RUNTESTFLAGS="i386.exp=gcc.target/i386/pr59539-1.c --target_board='unix{-m32\ -march=cascadelake}'"
$ cd {build_dir}/gcc && make check RUNTESTFLAGS="i386.exp=gcc.target/i386/pr59539-1.c --target_board='unix{-m64\ -march=cascadelake}'"

gcc/ChangeLog:

	* config/i386/sse.md (*avx2_pcmp<mode>3_1): Don't force_reg
	operands[3] when it's not const0_rtx.