[S390] is_power_of_2 in drivers/s390/block/dasd_int.h

Replacing n & (n - 1) for power of 2 check by is_power_of_2(n)
Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

drivers/s390/block/dasd_int.h

@@ -53,6 +53,7 @@
 #include <linux/genhd.h>
 #include <linux/hdreg.h>
 #include <linux/interrupt.h>
+#include <linux/log2.h>
 #include <asm/ccwdev.h>
 #include <linux/workqueue.h>
 #include <asm/debug.h>
@@ -456,7 +457,7 @@ dasd_free_chunk(struct list_head *chunk_list, void *mem)
 static inline int
 dasd_check_blocksize(int bsize)
 {
-	if (bsize < 512 || bsize > 4096 || (bsize & (bsize - 1)) != 0)
+	if (bsize < 512 || bsize > 4096 || !is_power_of_2(bsize))
 		return -EMEDIUMTYPE;
 	return 0;
 }