Expose remaining Avx512 integer intrinsics which don't require VectorMask

[tannergooding]

This exposes the last few Avx512 intrinsics that don't require VectorMask and makes progress towards completing:

• Expose System.Runtime.Intrinsics.X86.Avx512F.VL #74813
• Expose System.Runtime.Intrinsics.X86.Avx512F #73604
• Expose AVX512BW, AVX512CD, and AVX512DQ #76579

From the above, the only remaining APIs are the floating-point intrinsics that embed the rounding control. Covering these last few APIs is dependent on #84821, which adds the corresponding EVEX.b bit also used by embedded broadcasts.

I had thought I was going to need to cover Scatter/Gather as well, but the AVX-512 variants require use of the kmask registers to achieve functionality parity with the AVX variants and so are being pushed out alongside the VectorMask work.

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

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Issue Details

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This exposes the last few Avx512 intrinsics that don't require VectorMask and makes progress towards completing:

• Expose System.Runtime.Intrinsics.X86.Avx512F.VL #74813
• Expose System.Runtime.Intrinsics.X86.Avx512F #73604
• Expose AVX512BW, AVX512CD, and AVX512DQ #76579

From the above, the only remaining APIs are the floating-point intrinsics that embed the rounding control. Covering these last few APIs is dependent on #84821, which adds the corresponding EVEX.b bit also used by embedded broadcasts.

I had thought I was going to need to cover Scatter/Gather as well, but the AVX-512 variants require use of the kmask registers to achieve functionality parity with the AVX variants and so are being pushed out alongside the VectorMask work.

Author:	tannergooding
Assignees:	tannergooding
Labels:	area-CodeGen-coreclr, new-api-needs-documentation
Milestone:	-