[S390] tape: Add pr_fmt() macro to all tape source files

Without defining the pr_fmt() macro, the "tape: " prefix will not be
printed when using the pr_xxx printk macros. This patch adds the
missing definitions.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/tape_class.c b/drivers/s390/char/tape_class.c
index ddc914cc..b2864e3 100644
--- a/drivers/s390/char/tape_class.c
+++ b/drivers/s390/char/tape_class.c
@@ -7,6 +7,10 @@
  * Author: Stefan Bader <shbader@de.ibm.com>
  * Based on simple class device code by Greg K-H
  */
+
+#define KMSG_COMPONENT "tape"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
 #include "tape_class.h"
 
 MODULE_AUTHOR("Stefan Bader <shbader@de.ibm.com>");