JIT: Allow comparing GC pointers with `ccmp`

[jakobbotsch]

We currently use varTypeIsIntegral when checking for which kinds of operands we can compare with ccmp, but we should allow comparing GC pointers too (varTypeIsIntegralOrI).

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Issue Details

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We currently use varTypeIsIntegral when checking for which kinds of operands we can compare with ccmp, but we should allow comparing GC pointers too (varTypeIsIntegralOrI).

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

[jakobbotsch]

As part of this we should also double check that the GC reporting is correct for the instruction.