i386.c (standard_sse_constant_opcode): Use vpxord/vpternlog if avx512 is availible.

i386.c (standard_sse_constant_opcode): Use vpxord/vpternlog if avx512 is availible.

gcc/
	* config/i386/i386.c (standard_sse_constant_opcode): Use
	vpxord/vpternlog if avx512 is availible.

Co-Authored-By: Andrey Turetskiy <andrey.turetskiy@intel.com>
Co-Authored-By: Anna Tikhonova <anna.tikhonova@intel.com>
Co-Authored-By: Ilya Tocar <ilya.tocar@intel.com>
Co-Authored-By: Ilya Verbin <ilya.verbin@intel.com>
Co-Authored-By: Kirill Yukhin <kirill.yukhin@intel.com>
Co-Authored-By: Maxim Kuznetsov <maxim.kuznetsov@intel.com>
Co-Authored-By: Michael Zolotukhin <michael.v.zolotukhin@intel.com>
From-SVN: r213847