LoongArch: Fixed bug in *bstrins_<mode>_for_ior_mask template.

We found that using the latest compiled gcc will cause a miscompare error
when running spec2006 400.perlbench test with -flto turned on.  After testing,
it was found that only the LoongArch architecture will report errors.
The first error commit was located through the git bisect command as
r14-3773-g5b857e87201335.  Through debugging, it was found that the problem
was that the split condition of the *bstrins_<mode>_for_ior_mask template was
empty, which should actually be consistent with the insn condition.

gcc/ChangeLog:

	* config/loongarch/loongarch.md: Adjust.