i386: Fix endless recursion in ix86_expand_vector_init_general with MMX [PR110152]

i386: Fix endless recursion in ix86_expand_vector_init_general with MMX [PR110152]

I'm getting
+FAIL: gcc.target/i386/3dnow-1.c (internal compiler error: Segmentation fault signal terminated program cc1)
+FAIL: gcc.target/i386/3dnow-1.c (test for excess errors)
+FAIL: gcc.target/i386/3dnow-2.c (internal compiler error: Segmentation fault signal terminated program cc1)
+FAIL: gcc.target/i386/3dnow-2.c (test for excess errors)
+FAIL: gcc.target/i386/mmx-1.c (internal compiler error: Segmentation fault signal terminated program cc1)
+FAIL: gcc.target/i386/mmx-1.c (test for excess errors)
+FAIL: gcc.target/i386/mmx-2.c (internal compiler error: Segmentation fault signal terminated program cc1)
+FAIL: gcc.target/i386/mmx-2.c (test for excess errors)
regressions on i686-linux since r14-1166.  The problem is when
ix86_expand_vector_init_general is called with mmx_ok = true and
mode = V4HImode, it newly recurses with mmx_ok = false and mode = V2SImode,
but as mmx_ok is false and !TARGET_SSE, we recurse again with the same
arguments (ok, fresh new tmp and vals) infinitely.
The following patch fixes that by passing mmx_ok to that recursive call.
For n_words == 4 it isn't needed, because we only care about mmx_ok for
V2SImode or V2SFmode and no other modes.

2023-06-08  Jakub Jelinek  <jakub@redhat.com>

	PR target/110152
	* config/i386/i386-expand.cc (ix86_expand_vector_init_general): For
	n_words == 2 recurse with mmx_ok as first argument rather than false.