[media] av7110_hw: fix a sanity check in av7110_fw_cmd()

ARRAY_SIZE(buf) (8 elements) was intended instead of sizeof(buf) (16
bytes).  But this is just a sanity check and the callers always pass
valid values so this doesn't cause a problem.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/pci/ttpci/av7110_hw.c

@@ -501,7 +501,7 @@ int av7110_fw_cmd(struct av7110 *av7110, int type, int com, int num, ...)
 
 //	dprintk(4, "%p\n", av7110);
 
-	if (2 + num > sizeof(buf)) {
+	if (2 + num > ARRAY_SIZE(buf)) {
 		printk(KERN_WARNING
 		       "%s: %s len=%d is too big!\n",
 		       KBUILD_MODNAME, __func__, num);