Use named constants from a shared header instead of magic values when handling pseudo ops. Change-Id: If157060bbcd772ce7e8556482b44ca714f4319b1 Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/4262 Reviewed-by: Gabe Black <gabeblack@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>