Investigate removing gtSimdBaseJitType from GenTreeVecCon

[tannergooding]

#68874 introduced a new GenTreeVecCon node and it currently carries a gtSimdBaseJitType field so that a handle can be reconstituted where required.

As per #68874 (comment), #69971 likely removed the need to carry this information around and so we should remove the field if that is indeed the case.

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Issue Details

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#68874 introduced a new GenTreeVecCon node and it currently carries a gtSimdBaseJitType field so that a handle can be reconstituted where required.

As per #68874 (comment), #69971 likely removed the need to carry this information around and so we should remove the field if that is indeed the case.

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

[JulieLeeMSFT]

cc @dotnet/jit-contrib.