manta: add battery led support

Patchset 1: add led config flag
Patchset 2-4: fix whitespace issues

Change-Id: Ic54ac23350e7f18dc9fed59275bdd2e6f7115844
manta:  Updated branch name for kernel

Change-Id: I159b363337efcf11579eb0853994e7ca53e2bdc8
manta:  Fix branch name typo

Change-Id: I9feb39bf2a1e976082649a5b8de9f9951d80fc34
manta: Set TARGET_ARCH_VARIANT to cortex-a15

Change-Id: Iea43e322f8aa374ea69fc90f9d84a4c2c4c78750