phy: tegra: xusb: Fix return value of tegra_xusb_find_port_node function

callers of tegra_xusb_find_port_node() function only do NULL checking for
the return value. return NULL instead of ERR_PTR(-ENOMEM) to keep
consistent.
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20211213020507.1458-1-linmq006@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/phy/tegra/xusb.c

@@ -455,7 +455,7 @@ tegra_xusb_find_port_node(struct tegra_xusb_padctl *padctl, const char *type,
 	name = kasprintf(GFP_KERNEL, "%s-%u", type, index);
 	if (!name) {
 		of_node_put(ports);
-		return ERR_PTR(-ENOMEM);
+		return NULL;
 	}
 	np = of_get_child_by_name(ports, name);
 	kfree(name);