arm-bsp: u-boot: rebase a5ds patches

Rebase a5ds u-boot patches so, they apply clean in top of
latest u-boot.

Change-Id: I12e596ef8460429b540777e2a8646ed64f81fbac
Signed-off-by: Rui Miguel Silva <rui.silva@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>