[X86][NFC] Adding one flag to imply whether the instruction should check the predicate when compress EVEX instructions to VEX encoding.
Some EVEX instructions should check the predicates when compress to VEX
encoding. For example, avx512vnni instructions. This is because avx512vnni
doesn't mean that avxvnni is supported on the target.
This patch moving the manually added check to .inc that generated by tablegen.
Differential Revision: https://reviews.llvm.org/D98011