i386: Auto vectorize sdot_prod, usdot_prod, udot_prod with AVX10.2 instructions

gcc/ChangeLog:

	* config/i386/sse.md (VI1_AVX512VNNIBW): New.
	(VI2_AVX10_2): Ditto.
	(sdot_prod<mode>): Add AVX10.2
	to auto vectorize and combine 512 bit part.
	(udot_prod<mode>): Ditto.
	(sdot_prodv64qi): Removed.
	(udot_prodv64qi): Ditto.
	(usdot_prod<mode>): Add AVX10.2 to auto vectorize.
	(udot_prod<mode>): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/vnniint16-auto-vectorize-2.c: Only define
	TEST when not defined.
	* gcc.target/i386/vnniint8-auto-vectorize-2.c: Ditto.
	* gcc.target/i386/vnniint16-auto-vectorize-3.c: New test.
	* gcc.target/i386/vnniint16-auto-vectorize-4.c: Ditto.
	* gcc.target/i386/vnniint8-auto-vectorize-3.c: Ditto.
	* gcc.target/i386/vnniint8-auto-vectorize-4.c: Ditto.