cmd/compile: enforce strongly typed rules for ARM (1)
Remove type casting in:
L731 - L764, L772, L780 - L781, L1014 - L1054, L1057 - L1068, L1195, L1199
Toolstack-check successful.
Change-Id: I80f90716477f269a227be28b14bf913b78ef375d
Reviewed-on: https://go-review.googlesource.com/c/go/+/228824
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Giovanni Bajo <rasky@develer.com>