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

Try to mitigate potential future driver core api changes by adding
padding to a number of core internal scheduler structures.

Bug: 151154716
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0ef2f8dd5f3259dcf443c5045aa1e8505ed78a76