[source] ramips: pinctrl: return proper error if pinctrl0 is empty

[LEDE Commits]

mkresin pushed a commit to source.git, branch master:
https://git.lede-project.org/a3995a678551c699c9702ed28003c2ba868d2db1

commit a3995a678551c699c9702ed28003c2ba868d2db1
Author: Mathias Kresin <dev at kresin.me>
AuthorDate: Tue Jul 25 20:23:28 2017 +0200

    ramips: pinctrl: return proper error if pinctrl0 is empty
    
    Children of the pinctrl0 node are optional. Return EINVAL (=missing)
    instead of 0. Fixes a hang if the pinctrl0 has no children.
    
    Signed-off-by: Mathias Kresin <dev at kresin.me>
    Acked-by: John Crispin <john at phrozen.org>
---
 .../ramips/patches-4.9/0025-pinctrl-ralink-add-pinctrl-driver.patch     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/linux/ramips/patches-4.9/0025-pinctrl-ralink-add-pinctrl-driver.patch b/target/linux/ramips/patches-4.9/0025-pinctrl-ralink-add-pinctrl-driver.patch
index 6e0d643..dc45852 100644
--- a/target/linux/ramips/patches-4.9/0025-pinctrl-ralink-add-pinctrl-driver.patch
+++ b/target/linux/ramips/patches-4.9/0025-pinctrl-ralink-add-pinctrl-driver.patch
@@ -193,7 +193,7 @@ Signed-off-by: John Crispin <blogic at openwrt.org>
 +	}
 +
 +	if (!max_maps)
-+		return max_maps;
++		return -EINVAL;
 +
 +	*map = kzalloc(max_maps * sizeof(struct pinctrl_map), GFP_KERNEL);
 +	if (!*map)