arm64: remove assembly code string functions

Inconsistent progress was observed running ramstage.
It was determined that the hand-coded assembly functions
were causing issues. Some of the comments seems suspect about
the hardware taking care of alignment. The prudent thing to do
is to use the C ones. Optimization can come later after maturity.

BUG=chrome-os-partner:29923
BRANCH=None
TEST=Built and booted to attempting to payload

Original-Change-Id: I4137adf9b36b638ed207e4efd57adaac64c6a6c1
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/207431
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
(cherry picked from commit 2762e478c6b59dd30c59aa87a922d0f78c00c0c4)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: Id3196b0c2bf41a21db31f999ba437d118875a236
Reviewed-on: http://review.coreboot.org/8587
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins)
4 files changed