Fix test for tun device, -f fails because it's a char device, not a regular file. -e works.
Fix test for tun device, -f fails because it's a char device, not a regular file. -e works.

phil-davis/pfsense,jxmx/pfsense,NewEraCracker/pfsense,dennypage/pfsense,phil-davis/pfsense,NOYB/pfsense,pfsense/pfsense,ch1c4um/pfsense,NOYB/pfsense,NewEraCracker/pfsense,NewEraCracker/pfsense,ch1c4um/pfsense,jxmx/pfsense,pfsense/pfsense,ptorsten/pfsense,jxmx/pfsense,pfsense/pfsense,dennypage/pfsense,BlackstarGroup/pfsense,pfsense/pfsense,phil-davis/pfsense,BlackstarGroup/pfsense,BlackstarGroup/pfsense,dennypage/pfsense,brunostein/pfsense,brunostein/pfsense,ch1c4um/pfsense,ptorsten/pfsense,BlackstarGroup/pfsense,NewEraCracker/pfsense,ch1c4um/pfsense,phil-davis/pfsense,dennypage/pfsense,brunostein/pfsense,NOYB/pfsense,ptorsten/pfsense