[MachineOutliner] Don't outline ADRP pair to avoid incorrect ICF (#160232)

On AArch64, ADRP and its user instructions (LDR, ADD, etc.), that are
referencing a GOT symbol, when separated into different functions by
machine outliner exposes a correctness issue in the linker ICF. In such
cases, user instructions can end up pointing to a folded section (with
its canonical folded symbol), while ADRP instruction point to a GOT
entry corresponding to the original symbol. This leads to loading from
incorrect memory address after ICF. #129122 explains how this can happen
in detail.

This addresses #131660 which should fix two things:
1. Hide the correctness issue described above in the LLVM linker.
2. Allows optimizations that could relax GOT addressing to PC-relative
addressing.

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