i386: Fix up V32HImode permutations with -mno-avx512bw [PR101860]

i386: Fix up V32HImode permutations with -mno-avx512bw [PR101860]

My patch from yesterday apparently broke some V32HImode permutations
as the testcase shows.
The first function assumed it would never be called in d->testing_p mode
and so went right away into emitting the code.
And the second one assumed V32HImode would never reach it, which now
can for the !TARGET_AVX512BW case.  We don't have a instruction
in that case though.

2021-08-12  Jakub Jelinek  <jakub@redhat.com>

	PR target/101860
	* config/i386/i386-expand.c (ix86_expand_vec_one_operand_perm_avx512):
	If d->testing_p, return true after performing checks instead of
	actually expanding the insn.
	(expand_vec_perm_broadcast_1): Handle V32HImode - assert
	!TARGET_AVX512BW and return false.

	* gcc.target/i386/avx512f-pr101860.c: New test.