ANDROID: fix overwrite and increase the memory gap for kernel and initramfs

This is a redo for commit 2095a16d14fb8f050bb34684ac70683af6274f37 and
commit 317b196d4f4c6670f1482a6945fcf47ae009af62. Let all the architecture
uses the same setup. And the gap is calculated by the size of the kernel.

Change-Id: I13ef858451ec6d72553a2d172864e3d789e753e6
Signed-off-by: Ying-Chun Liu <liupa@google.com>
2 files changed