[AArch64] Treat the icmp in icmp(and(..), 0) as free

As in https://godbolt.org/z/4dafd9Geq, the icmp from an And may use an Ands to
set flags, meaning the icmp is free.

This could also be done for add/sub, but those patterns often happen in the
induction variable of a loop, making them quite performance sensitive.

Differential Revision: https://reviews.llvm.org/D153611