s390/crypto: fix possible sleep during spinlock aquired
This patch fixes a complain about possible sleep during
spinlock aquired
"BUG: sleeping function called from invalid context at
include/crypto/algapi.h:426"
for the ctr(aes) and ctr(des) s390 specific ciphers.
Instead of using a spinlock this patch introduces a mutex
which is save to be held in sleeping context. Please note
a deadlock is not possible as mutex_trylock() is used.