[ARM] Prevent constants from iCmp instruction from being hoisted if part of a min(max()) pattern

Marks constants of an ICmp instruction as free if it's only user is a select
instruction that is part of a min(max()) pattern. Ensures that in loops, in
particular when loop unrolling is turned on, SSAT will still be correctly generated.

Differential Revision: https://reviews.llvm.org/D88662