i386: Use ix86_output_ssemov for DFmode TYPE_SSEMOV

i386: Use ix86_output_ssemov for DFmode TYPE_SSEMOV

There is no need to set mode attribute to XImode nor V8DFmode since
ix86_output_ssemov can properly encode xmm16-xmm31 registers with and
without AVX512VL.

gcc/

	PR target/89229
	* config/i386/i386.c (ix86_output_ssemov): Handle MODE_DF.
	* config/i386/i386.md (*movdf_internal): Call ix86_output_ssemov
	for TYPE_SSEMOV.  Remove TARGET_AVX512F, TARGET_PREFER_AVX256,
	TARGET_AVX512VL and ext_sse_reg_operand check.

gcc/testsuite/

	PR target/89229
	* gcc.target/i386/pr89229-4a.c: New test.
	* gcc.target/i386/pr89229-4b.c: Likewise.
	* gcc.target/i386/pr89229-4c.c: Likewise.