rcu: Check the return value of zalloc_cpumask_var()
rcu: Check the return value of zalloc_cpumask_var()

This commit checks the return value of the zalloc_cpumask_var() used for
allocating cpumask for rcu_nocb_mask.

Signed-off-by: Pranith Kumar <99f39d96f0d0b011d351b608fe7e2870596fa4a9@gmail.com>
Signed-off-by: Paul E. McKenney <1e0ce936bb9b355d257bf5790d2513c3f28be22b@linux.vnet.ibm.com>
Tested-by: Paul Gortmaker <ae947f3c8df96e1dc851c5e3e5a930ce6d3f1f74@windriver.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs