arm64: split cpu.c

The cpu.c contains some helpful construts as well as ramstage
devicetree handling. Split the 2 pieces so that cpu.c can be
reused in secmon.

BUG=chrome-os-partner:30785
BRANCH=None
TEST=Built and booted.

Change-Id: Iec0f8462411897a255f7aa289191ce6761e08bb0
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 4f30f1186950424b65df6858965a09ca51637e4f
Original-Change-Id: Ie87bd35bf1ccd777331250dcdaae07dab82d3d18
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/218842
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9089
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
4 files changed