Normalize the creation of simd comparison nodes and give basic constant folding support

[tannergooding]

This ensures that SIMD comparison nodes are consistently created and gives basic constant folding support to them.

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[tannergooding]

CC. @dotnet/jit-contrib, this should also be ready for review.

It ensures that SIMD Compare nodes are consistently created and adds the basic recognition of them to HWOperGet which allows them to plug into the existing binary constant folding support.

There's some nice codegen wins, which can be improved further in a follow up PR by ensuring that op_Equality and op_Inequality are also handled. These require special handling, however, since they produce bool instead of a SIMD result.

[kunalspathak]

codegen diffs looks great. LGTM