s390/qdio: rework BUG's and WARN_ON's

Remove or replace BUG/BUG_ON where possible and convert WARN_ON
to WARN_ON_ONCE if they can occur freqeuently as pointed out by:
https://lkml.org/lkml/2012/9/27/461

Checks have been removed if:
- the error condition leads to a hardware error which gets logged
  and in most cases stops the device
- the error condition is a null pointer access
- the error condition is just pointless or already handled at
  another location

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/qdio_setup.c b/drivers/s390/cio/qdio_setup.c
index 6c973db..6559564 100644
--- a/drivers/s390/cio/qdio_setup.c
+++ b/drivers/s390/cio/qdio_setup.c
@@ -140,10 +140,8 @@
 	q->sl = (struct sl *)((char *)q->slib + PAGE_SIZE / 2);
 
 	/* fill in sbal */
-	for (j = 0; j < QDIO_MAX_BUFFERS_PER_Q; j++) {
+	for (j = 0; j < QDIO_MAX_BUFFERS_PER_Q; j++)
 		q->sbal[j] = *sbals_array++;
-		BUG_ON((unsigned long)q->sbal[j] & 0xff);
-	}
 
 	/* fill in slib */
 	if (i > 0) {