After removing the batman-adv module, the hash may be already gone
when tt_global_del_orig() tries to clean the hash. This patch adds
a sanity check to avoid this.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Tested-by: NAlexey Fisher <bug-track@fisher-privat.net>
Signed-off-by: NMarek Lindner <lindner_marek@yahoo.de>