[S390] tape: New read configuration data.

Instead of the deprecated read_conf_data(), implement a new function
tape_3590_read_dev_chars().

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/tape.h b/drivers/s390/char/tape.h
index bb4ff53..3b52f5c 100644
--- a/drivers/s390/char/tape.h
+++ b/drivers/s390/char/tape.h
@@ -103,6 +103,7 @@
 	TO_CRYPT_OFF,	/* Disable encrpytion */
 	TO_KEKL_SET,	/* Set KEK label */
 	TO_KEKL_QUERY,	/* Query KEK label */
+	TO_RDC,		/* Read device characteristics */
 	TO_SIZE,	/* #entries in tape_op_t */
 };