Ensure that the VNFunc for HWIntrinsics are properly marked as commutative where possible

[tannergooding]

This ensures that VN recognizes commutative HWIntrinsics as commutative. It not being set is likely why #75818 had no diffs.

Notably there are some intrinsics which are "maybe commutative". These either require special handling (due to taking more than 2 operands) or require checking that one of the inputs is constant and within the bounds of a particular optimization. Such intrinsics aren't being handled as part of this change.

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Issue Details

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This ensures that VN recognizes commutative HWIntrinsics as commutative. It not being set is likely why #75818 had no diffs.

Author:	tannergooding
Assignees:	-
Labels:	area-CodeGen-coreclr
Milestone:	-

[tannergooding]

It found a couple of small diffs due to new CSEs, but only in tests.

Linux Arm64:

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 490656816 (overridden on cmd)
Total bytes of diff: 490656792 (overridden on cmd)
Total bytes of delta: -24 (-0.00 % of base)
    diff is an improvement.
    relative diff is an improvement.

Windows x64:

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 322064734 (overridden on cmd)
Total bytes of diff: 322064717 (overridden on cmd)
Total bytes of delta: -17 (-0.00 % of base)
    diff is an improvement.
    relative diff is an improvement.

User code may see more improvements.

[tannergooding]

CC. @dotnet/jit-contrib. A small/minor change.