[X86] Correct the scheduling information for AVX-VNNI and AVX512-VNNI instructons.

The AVXVNNI load instructions weren't using the Folded load write
class and they had no ReadAdvance.
The YMM versions were using the XMM schedule class.

The AVX512VNNI instructions had the right classes, but not enough
ReadAdvances to account for the 2 sources.

Noticed while investigating #62026.

Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D147872