btrfs: use common helpers for extent IO state insertion messages

Print the error messages using the helpers that also print the
filesystem identification.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent_io.c

@@ -522,9 +522,11 @@ static int insert_state(struct extent_io_tree *tree,
 {
 	struct rb_node *node;
 
-	if (end < start)
-		WARN(1, KERN_ERR "BTRFS: end < start %llu %llu\n",
-		       end, start);
+	if (end < start) {
+		btrfs_err(tree->fs_info,
+			"insert state: end < start %llu %llu", end, start);
+		WARN_ON(1);
+	}
 	state->start = start;
 	state->end = end;
 
@@ -534,7 +536,8 @@ static int insert_state(struct extent_io_tree *tree,
 	if (node) {
 		struct extent_state *found;
 		found = rb_entry(node, struct extent_state, rb_node);
-		pr_err("BTRFS: found node %llu %llu on insert of %llu %llu\n",
+		btrfs_err(tree->fs_info,
+		       "found node %llu %llu on insert of %llu %llu",
 		       found->start, found->end, start, end);
 		return -EEXIST;
 	}