[S390] zcore: add missing module.h include

Add missing module.h include to prevent build breakage after the
module.h split work hits Linus' tree.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/zcore.c

@@ -16,6 +16,7 @@
 #include <linux/slab.h>
 #include <linux/miscdevice.h>
 #include <linux/debugfs.h>
+#include <linux/module.h>
 #include <asm/asm-offsets.h>
 #include <asm/ipl.h>
 #include <asm/sclp.h>