aries | p1: switch the protection of percpu_counter list to spinlock

... making percpu_counter_destroy() non-blocking

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Change-Id: I098fb1393f24a0f2234ccd23c149c8bc15c31276
Merge "aries | p1: switch the protection of percpu_counter list to spinlock" into android-4.4