[NOP] removed redundant code

The Log4j file appender will create the missing directories by itself so
there is no need to implement this behavior again.

Change-Id: Ic0dc7c712e200380b6d36b1d1d06cd1d4db0d008
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1404
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>