olsrd: hotplug: optimize execution-speed and simplify using already existing GLOBAL vars instead of encapsulating vars from function to function, cleanups and comments in source
olsrd: hotplug: changed a varname which broke in 3a1fd118833e8c6d341fde4ef99d31786c3614c9
luci-app-bmx6: Initialize tun6in6 variable and add further checks

Signed-off-by: Pau Escrich <p4u@dabax.net>