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

Try to mitigate potential future driver core api changes by adding a
pointer to struct signal_struct, struct sched_entity, struct
sched_rt_entity, and struct task_struct.

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

Leaf changes summary: 3 artifacts changed
Changed leaf types summary: 3 leaf types changed
Removed/Changed/Added functions summary: 0 Removed, 0 Changed, 0 Added function
Removed/Changed/Added variables summary: 0 Removed, 0 Changed, 0 Added variable

'struct sched_entity at sched.h:444:1' changed:
  type size changed from 3584 to 4096 (in bits)
  4 data member insertions:
    'u64 sched_entity::android_kabi_reserved1', at offset 3584 (in bits) at sched.h:481:1
    'u64 sched_entity::android_kabi_reserved2', at offset 3648 (in bits) at sched.h:482:1
    'u64 sched_entity::android_kabi_reserved3', at offset 3712 (in bits) at sched.h:483:1
    'u64 sched_entity::android_kabi_reserved4', at offset 3776 (in bits) at sched.h:484:1
  1435 impacted interfaces:

'struct sched_rt_entity at sched.h:481:1' changed:
  type size changed from 384 to 640 (in bits)
  4 data member insertions:
    'u64 sched_rt_entity::android_kabi_reserved1', at offset 384 (in bits) at sched.h:504:1
    'u64 sched_rt_entity::android_kabi_reserved2', at offset 448 (in bits) at sched.h:505:1
    'u64 sched_rt_entity::android_kabi_reserved3', at offset 512 (in bits) at sched.h:506:1
    'u64 sched_rt_entity::android_kabi_reserved4', at offset 576 (in bits) at sched.h:507:1
  1435 impacted interfaces:

'struct task_struct at sched.h:624:1' changed:
  type size changed from 28672 to 30208 (in bits)
  8 data member insertions:
    'u64 task_struct::android_kabi_reserved1', at offset 20992 (in bits) at sched.h:1294:1
    'u64 task_struct::android_kabi_reserved2', at offset 21056 (in bits) at sched.h:1295:1
    'u64 task_struct::android_kabi_reserved3', at offset 21120 (in bits) at sched.h:1296:1
    'u64 task_struct::android_kabi_reserved4', at offset 21184 (in bits) at sched.h:1297:1
    'u64 task_struct::android_kabi_reserved5', at offset 21248 (in bits) at sched.h:1298:1
    'u64 task_struct::android_kabi_reserved6', at offset 21312 (in bits) at sched.h:1299:1
    'u64 task_struct::android_kabi_reserved7', at offset 21376 (in bits) at sched.h:1300:1
    'u64 task_struct::android_kabi_reserved8', at offset 21440 (in bits) at sched.h:1301:1
  there are data member changes:
  1435 impacted interfaces:

Bug: 151154716
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I1449735b836399e9b356608727092334daf5c36b