dm: don't report "detected capacity change" on device creation

When a DM device is first created it doesn't yet have an established
capacity, therefore the use of set_capacity_and_notify() should be
conditional given the potential for needless pr_info "detected
capacity change" noise even if capacity is 0.

One could argue that the pr_info() in set_capacity_and_notify() is
misplaced, but that position is not held uniformly.

Signed-off-by: Mikulas Patocka <[e-mail]>
Fixes: f64d9b2eacb9 ("dm: use set_capacity_and_notify")
Cc: [e-mail]
Signed-off-by: Mike Snitzer <[e-mail]>

drivers/md/dm.c

···
 	if (size != dm_get_size(md))
 		memset(&md->geometry, 0, sizeof(md->geometry));
 
-	set_capacity_and_notify(md->disk, size);
+	if (!get_capacity(md->disk))
+		set_capacity(md->disk, size);
+	else
+		set_capacity_and_notify(md->disk, size);
 
 	dm_table_event_callback(t, event_callback, md);