Changes for new version of image loading in BL1/BL2

This patch adds changes in BL1 & BL2 to use new version
of image loading to load the BL images.

Following are the changes in BL1:
-Use new vers

Changes for new version of image loading in BL1/BL2

This patch adds changes in BL1 & BL2 to use new version
of image loading to load the BL images.

Following are the changes in BL1:
-Use new version of load_auth_image() to load BL2
-Modified `bl1_init_bl2_mem_layout()` to remove using
`reserve_mem()` and to calculate `bl2_mem_layout`.
`bl2_mem_layout` calculation now assumes that BL1 RW
data is at the top of the bl1_mem_layout, which is more
restrictive than the previous BL1 behaviour.

Following are the changes in BL2:
-The `bl2_main.c` is refactored and all the functions
for loading BLxx images are now moved to `bl2_image_load.c`
`bl2_main.c` now calls a top level `bl2_load_images()` to
load all the images that are applicable in BL2.
-Added new file `bl2_image_load_v2.c` that uses new version
of image loading to load the BL images in BL2.

All the above changes are conditionally compiled using the
`LOAD_IMAGE_V2` flag.

Change-Id: Ic6dcde5a484495bdc05526d9121c59fa50c1bf23

show more ...