[S390] cio: Get rid of css_characteristics_avail.

Checking for the validity of the css_*_characteristics is
superfluous since they stay 0 for non-successful scsc.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index 6c77c23..7752313 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -1344,8 +1344,7 @@
 	 * to basic mode.
 	 */
 	if (format == CMF_AUTODETECT) {
-		if (!css_characteristics_avail ||
-		    !css_general_characteristics.ext_mb) {
+		if (!css_general_characteristics.ext_mb) {
 			format = CMF_BASIC;
 		} else {
 			format = CMF_EXTENDED;