Revert "sched: Change nr_uninterruptible type to unsigned long"

This reverts commit 7fc808d9 which is
commit 36569780 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ib3c5080b3545cf26a5ef26e9f7f2f3ea79b701a4
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>