ARM: dts: msm: Migrate 8x74 memory regions to CMA

CMA now fully supports removing regions from memory. Since CMA
is the preferred method for tracking these regions as well, migrate
all removed regions over to use CMA and CMA derivatives.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
[neo: This patch is modified to skip external_image_mem
 region which I am really not sure where it is used.]
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>