[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_proc.c b/drivers/s390/char/tape_proc.c
index ebd820c..0ceb379 100644
--- a/drivers/s390/char/tape_proc.c
+++ b/drivers/s390/char/tape_proc.c
@@ -11,6 +11,9 @@
  * PROCFS Functions
  */
 
+#define KMSG_COMPONENT "tape"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
 #include <linux/module.h>
 #include <linux/vmalloc.h>
 #include <linux/seq_file.h>