cpufeatures: requesting support for the newly added target features

[sayantn]

Some new target features were added to Rust

• Expand avx512_target_feature to include VEX variants rust-lang/rust#126617 avxifma, avxvnni, avxvnniint8, avxvnniint16 and avxneconvert
• Add AMX target-features and x86_amx_intrinsics feature flag rust-lang/rust#126639 amx-tile, amx-int8, amx-bf16, amx-fp16 and amx-complex
• Added SHA512, SM3, SM4 target-features and sha512_sm_x86 feature gate rust-lang/rust#126704 sha512, sm3 and sm4
• rustc_target: Add various aarch64 features rust-lang/rust#128192 many new AArch64 target features

[tarcieri]

TIL there are SHA-512 intrinsics for x86 CPUs. Apparently only for Arrow Lake and Lunar Lake:

https://en.wikipedia.org/wiki/Intel_SHA_extensions

• VSHA512RNDS2
• VSHA512MSG1
• VSHA512MSG2