s390/zcore: Removed unused variables

s390/zcore: Removed unused variables

allmodconfig with clang W=1 points out unused global variables:

drivers/s390/char/zcore.c:49:23: error: variable
 'zcore_reipl_file' set but not used [-Werror,-Wunused-but-set-global]
drivers/s390/char/zcore.c:50:23: error: variable
 'zcore_hsa_file' set but not used [-Werror,-Wunused-but-set-global]

Remove both of them, since there is no point in keeping them.

Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>