[PATCH] block: Use NULL to compare with pointer-typed value rather than 0

We should use NULL to compare with pointer-typed value rather than
0. The issue is detected with the help of Coccinelle.

Signed-off-by: zhong jiang <redacted>
---
 drivers/block/ataflop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index dfb2c26..cca93e3 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c

@@ -1355,7 +1355,7 @@ static int floppy_revalidate(struct gendisk *disk)
 
 	if (test_bit(drive, &changed_floppies) ||
 	    test_bit(drive, &fake_change) ||
-	    p->disktype == 0) {
+	    p->disktype == NULL) {
 		if (UD.flags & FTD_MSG)
 			printk(KERN_ERR "floppy: clear format %p!\n", UDT);
 		BufferDrive = -1;