"[[" is a bash extension for test. As the ash-implementation is not
fully compatible we drop its usage.
Signed-off-by: Sven Roederer <devel-sven@geroedel.de>
[remove shebang, slightly facelift commit title/message]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
3519bf4976