[PATCH] Add Sparse annotations to SRCU wrapper functions in rcutorture

The SRCU wrapper functions srcu_torture_read_lock and
srcu_torture_read_unlock in rcutorture intentionally change the SRCU
context; annotate them accordingly, to avoid a warning.

Signed-off-by: Josh Triplett <josh@freedesktop.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>