drm: bridge: it66121: fix a resource leak in probe

In the original code if the "ctx = devm_kzalloc()" allocation failed
then we should have called of_node_put(ep); before returning.  It's
actually a bit easier to do the allocation first before assigning
ep = of_graph_get_endpoint_by_regs().

Fixes: 988156dc ("drm: bridge: add it66121 driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/YJ+ZgXTFa6voZuJG@mwanda

drivers/gpu/drm/bridge/ite-it66121.c

@@ -898,14 +898,14 @@ static int it66121_probe(struct i2c_client *client,
 		return -ENXIO;
 	}
 
-	ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
-	if (!ep)
-		return -EINVAL;
-
 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
 	if (!ctx)
 		return -ENOMEM;
 
+	ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
+	if (!ep)
+		return -EINVAL;
+
 	ctx->dev = dev;
 	ctx->client = client;