cmd/compile: Add shiftIsBounded check for logic shifts of arm64

cmd/compile: Add shiftIsBounded check for logic shifts of arm64

This CL adds shiftIsBounded checks for the Lsh* and Rsh* rules in arm64.
There is no need to check the shift value again with CMP + CSEL when the
shift value is valid.

Change-Id: I54620de64f02a1b5a11089add237248ae2de01b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/417714
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>