[AArch64][NFC] Fix ComplexPattern types conflicting with uses

[AArch64][NFC] Fix ComplexPattern types conflicting with uses

When used as a non-leaf node, TableGen does not currently use the type
of a ComplexPattern for type inference, which also means it does not
check it doesn't conflict with the use. This differs from when used as a
leaf value, where the type is used for inference. Fixing that
discrepancy is something I intend to upstream as a subsequent review,
but these are all the type conflicts found (all legitimate) by my
locally-patched TableGen.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D108759