testsuite: i386: Don't restrict gcc.dg/vect/vect-simd-clone-16c.c etc. to i686 [PR113556]

A couple of gcc.dg/vect/vect-simd-clone-1*.c tests FAIL on 32-bit
Solaris/x86 since 20230222:

FAIL: gcc.dg/vect/vect-simd-clone-16c.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2
FAIL: gcc.dg/vect/vect-simd-clone-16d.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2
FAIL: gcc.dg/vect/vect-simd-clone-17c.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2
FAIL: gcc.dg/vect/vect-simd-clone-17d.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2
FAIL: gcc.dg/vect/vect-simd-clone-18c.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2
FAIL: gcc.dg/vect/vect-simd-clone-18d.c scan-tree-dump-times vect
"[\\\\n\\\\r] [^\\\\n]* = foo\\\\.simdclone" 2

The problem is that the 32-bit Solaris/x86 triple still uses i386,
although gcc defaults to -mpentium4.  However, the tests only handle
x86_64* and i686*, although the tests don't seem to require some
specific ISA extension not covered by vect_simd_clones.

To fix this, the tests now allow generic i?86.  At the same time, I've
removed the wildcards from x86_64* and i686* since DejaGnu uses the
canonical forms.

Tested on i386-pc-solaris2.11 and i686-pc-linux-gnu.

2024-01-24  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	gcc/testsuite:
	PR target/113556
	* gcc.dg/vect/vect-simd-clone-16c.c: Don't wildcard x86_64 in
	target specs.  Allow any i?86 target instead of i686 only.
	* gcc.dg/vect/vect-simd-clone-16d.c: Likewise.
	* gcc.dg/vect/vect-simd-clone-17c.c: Likewise.
	* gcc.dg/vect/vect-simd-clone-17d.c: Likewise.
	* gcc.dg/vect/vect-simd-clone-18c.c: Likewise.
	* gcc.dg/vect/vect-simd-clone-18d.c: Likewise.