Fix standard name for zero/sign extend expanders

Fix standard name for zero/sign extend expanders

gcc/ChangeLog:

	* config/i386/i386.md (optab): New code attr.
	* config/i386/sse.md (<code>v32qiv32hi2): Rename to ...
	(<optab>v32qiv32hi2) ... this.
	(<code>v16qiv16hi2): Likewise.
	(<code>v8qiv8hi2): Likewise.
	(<code>v16qiv16si2): Likewise.
	(<code>v8qiv8si2): Likewise.
	(<code>v4qiv4si2): Likewise.
	(<code>v16hiv16si2): Likewise.
	(<code>v8hiv8si2): Likewise.
	(<code>v4hiv4si2): Likewise.
	(<code>v8qiv8di2): Likewise.
	(<code>v4qiv4di2): Likewise.
	(<code>v2qiv2di2): Likewise.
	(<code>v8hiv8di2): Likewise.
	(<code>v4hiv4di2): Likewise.
	(<code>v2hiv2di2): Likewise.
	(<code>v8siv8di2): Likewise.
	(<code>v4siv4di2): Likewise.
	(<code>v2siv2di2): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr92658-avx2-2.c: New test.
	* gcc.target/i386/pr92658-avx512bw-2.c: Likewise.
	* gcc.target/i386/pr92658-sse4-2.c: Likewise.