block: Replace function name in string with __func__

Replace hard coded function name register_blkdev with __func__, to
improve robustness and to conform to the Linux kernel coding
style. Issue found using checkpatch.
Signed-off-by: Keyur Patel <iamkeyur96@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/genhd.c

@@ -365,8 +365,8 @@ int register_blkdev(unsigned int major, const char *name)
 		}
 
 		if (index == 0) {
-			printk("register_blkdev: failed to get major for %s\n",
-			       name);
+			printk("%s: failed to get major for %s\n",
+			       __func__, name);
 			ret = -EBUSY;
 			goto out;
 		}
@@ -375,8 +375,8 @@ int register_blkdev(unsigned int major, const char *name)
 	}
 
 	if (major >= BLKDEV_MAJOR_MAX) {
-		pr_err("register_blkdev: major requested (%u) is greater than the maximum (%u) for %s\n",
-		       major, BLKDEV_MAJOR_MAX-1, name);
+		pr_err("%s: major requested (%u) is greater than the maximum (%u) for %s\n",
+		       __func__, major, BLKDEV_MAJOR_MAX-1, name);
 
 		ret = -EINVAL;
 		goto out;