ANDROID: GKI: mm: add Android ABI padding to some structures

Try to mitigate potential future driver core api changes by adding a
padding to stuct vm_area_struct and struct zone.

Based on a patch from Michal Marek <mmarek@suse.cz> from the SLES kernel

Bug: 151154716
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I81702aa833f419928e0e32e9609722b98592c171