Since commit a162dfe the ifup command runs
this file as a script. Due to a hush misbehave it could happen it returns
an error code by accident.

For example if the last instructions in this file are:

 if [ false ]; then
    echo "friesel"
 fi

the hush returns 1 after running this script instead of 0 and in this case
the ifup command fails.

I know, the correct fix would be to fix the hush, because it is a generic
issue...but how?

Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>