srcu: Add contention check to call_srcu() srcu_data ->lock acquisition

This commit increases the sensitivity of contention detection by adding
checks to the acquisition of the srcu_data structure's lock on the
call_srcu() code path.

Co-developed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>