41333ab uci: tighten uci reorder operation error handling
f91751b uci: tighten uci delete operation error handling
c2c612b uci: tighten uci set operation error handling
948bb51 uci: tighten uci add operation error handling
51980c6 uci: reject invalid section and option names

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
(cherry picked from commit 8c918072)