s390/jump_label: make use of HAVE_JUMP_LABEL_BATCH

Specify HAVE_JUMP_LABEL_BATCH in header file. This allows to make use
of the arch_jump_label_transform_queue()/arch_jump_label_transform_apply()
mechanism.

However unlike on x86, which currently is the only user of this
mechanism, the to be patched instructions are still directly
modified. The only difference to before is that serialization is only
done after all instructions have been modified. This way the number of
serialization/synchronization events is reduced.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>