s390: fix GENERIC_LOCKBREAK dependency typo in Kconfig

Commit fa686453 ("sched/rt, s390: Use CONFIG_PREEMPTION")
changed a bunch of uses of CONFIG_PREEMPT to _PREEMPTION.
Except in the Kconfig it used two T's. That's the only place
in the system where that spelling exists, so let's fix that.

Fixes: fa686453 ("sched/rt, s390: Use CONFIG_PREEMPTION")
Cc: <stable@vger.kernel.org> # 5.6
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>