ANDROID: GKI: blk_types.h: add Android ABI padding to a structure

Try to mitigate potential future driver core api changes by adding a
padding to struct bio.

Based on a change made to the RHEL/CENTOS 8 kernel.

Bug: 151154716
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ib69c7bb8b553cacb9cb7bc020d8ac2bbc75621ba