mwan3: remove not needes jshn.sh include

Remove not needed jshn.sh include.

Signed-off-by: Florian Eckert <fe@dev.tdt.de>

net/mwan3/files/etc/hotplug.d/iface/15-mwan3

@@ -3,7 +3,6 @@
 . /lib/functions.sh
 . /lib/functions/network.sh
 . /lib/mwan3/mwan3.sh
-. /usr/share/libubox/jshn.sh
 . /lib/mwan3/common.sh
 
 SCRIPTNAME="mwan3-hotplug"