[PATCH for request_api branch] v4l2-ctrls.c: fix smatch error

[Hans Verkuil]

Fix this smatch error:

drivers/media/v4l2-core/v4l2-ctrls.c:2971 v4l2_ctrl_request_clone() error: 
uninitialized symbol 'err'.

Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
---
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c 
b/drivers/media/v4l2-core/v4l2-ctrls.c
index 73665c7d7045..65e3cf838ac7 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -2942,7 +2942,7 @@ static int v4l2_ctrl_request_clone(struct 
v4l2_ctrl_handler *hdl,
                                   const struct v4l2_ctrl_handler *from)
 {
        struct v4l2_ctrl_ref *ref;
-       int err;
+       int err = 0;

        if (WARN_ON(!hdl || hdl == from))
                return -EINVAL;