arm64: Use Normal NonCacheable memory for writecombine

arm64: Use Normal NonCacheable memory for writecombine

commit 4f00130b70e5eee813cc7bc298e0f3fdf79673cc upstream.

This provides better performance compared to Device GRE and also allows
unaligned accesses. Such memory is intended to be used with standard RAM
(e.g. framebuffers) and not I/O.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 3655a197b1ea3ce989d34868768c5f4b6205061c)
Signed-off-by: Mark Brown <broonie@linaro.org>