[i386] APX: Fix ICE due to movti postreload splitter [PR112394]

[i386] APX: Fix ICE due to movti postreload splitter [PR112394]

When APX EGPR enabled, the TImode move pattern *movti_internal allows
move between gpr and sse reg using constraint pair ("r","Yd"). Then a
post-reload splitter transform such move to vec_extractv2di, while under
-msse4.1 -mno-avx EGPR is not allowed for its enabled alternative, which
caused ICE that insn does not match the constraint. To prevent such ICE,
we need to adjust the constraint correspond to "Yd". Add a new
constraint "jc" to disable EGPR under -mno-avx.

gcc/ChangeLog:

	PR target/112394
	* config/i386/constraints.md (jc): New constraint that prohibits
	EGPR on -mno-avx.
	* config/i386/i386.md (*movdi_internal): Change r constraint
	corresponds to Yd.
	(*movti_internal): Likewise.

gcc/testsuite/ChangeLog:

	PR target/112394
	* gcc.target/i386/pr112394.c: New test.