i386: Use ix86_output_ssemov for SImode TYPE_SSEMOV

i386: Use ix86_output_ssemov for SImode TYPE_SSEMOV

There is no need to set mode attribute to XImode since ix86_output_ssemov
can properly encode xmm16-xmm31 registers with and without AVX512VL.

Remove ext_sse_reg_operand since it is no longer needed.

gcc/

	PR target/89229
	* config/i386/i386.md (*movsi_internal): Call ix86_output_ssemov
	for TYPE_SSEMOV.  Remove ext_sse_reg_operand and TARGET_AVX512VL
	check.
	* config/i386/predicates.md (ext_sse_reg_operand): Removed.

gcc/testsuite/

	PR target/89229
	* gcc.target/i386/pr89229-7a.c: New test.
	* gcc.target/i386/pr89229-7b.c: Likewise.
	* gcc.target/i386/pr89229-7c.c: Likewise.