Properly check the parent's MTU when changing a VLAN MTU.
Properly check the parent's MTU when changing a VLAN MTU.

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