UPSTREAM: arm64: module: avoid undefined shift behavior in reloc_data()

UPSTREAM: arm64: module: avoid undefined shift behavior in reloc_data()

Compilers may engage the improbability drive when encountering shifts
by a distance that is a multiple of the size of the operand type. Since
the required bounds check is very simple here, we can get rid of all the
fuzzy masking, shifting and comparing, and use the documented bounds
directly.

Change-Id: Ibc1b73f4a630bc182deb6edfa7458b5e29ba9577
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>