conf: split <forward> parser/clear into separate functions
conf: split <forward> parser/clear into separate functions

virNetworkDefUpdateForward requires separate functions to parse and
clear a virNetworkForwardDef by itself, but they were previously just
inlined in the virNetworkDef parse and free functions. This patch
makes them into separate functions.

nertpinx/libvirt,andreabolognani/libvirt,bjzhang/libvirt,jardasgit/libvirt,libvirt/libvirt,crobinso/libvirt,zippy2/libvirt,iam-TJ/libvirt,datto/libvirt,andreabolognani/libvirt,olafhering/libvirt,zippy2/libvirt,eskultety/libvirt,bjzhang/libvirt,andreabolognani/libvirt,iam-TJ/libvirt,zhlcindy/libvirt-1.1.4-maintain,taget/libvirt,jfehlig/libvirt,siboulet/libvirt-openvz,zhlcindy/libvirt-1.1.4-maintain,cbosdo/libvirt,cbosdo/libvirt,datto/libvirt,olafhering/libvirt,nertpinx/libvirt,jfehlig/libvirt,crobinso/libvirt,zippy2/libvirt,agx/libvirt,rlaager/libvirt,taget/libvirt,libvirt/libvirt,libvirt/libvirt,elmarco/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,jeckersb/libvirt,fabianfreyer/libvirt,bjzhang/libvirt,zhlcindy/libvirt-1.1.4-maintain,taget/libvirt,VenkatDatta/libvirt,eskultety/libvirt,siboulet/libvirt-openvz,trainstack/libvirt,trainstack/libvirt,iam-TJ/libvirt,jfehlig/libvirt,cbosdo/libvirt,jfehlig/libvirt,shugaoye/libvirt,andreabolognani/libvirt,nertpinx/libvirt,zhlcindy/libvirt-1.1.4-maintain,fabianfreyer/libvirt,iam-TJ/libvirt,agx/libvirt,datto/libvirt,cbosdo/libvirt,iam-TJ/libvirt,datto/libvirt,bjzhang/libvirt,emaste/libvirt,datto/libvirt,agx/libvirt,trainstack/libvirt,fabianfreyer/libvirt,zhlcindy/libvirt-1.1.4-maintain,shugaoye/libvirt,emaste/libvirt,shugaoye/libvirt,elmarco/libvirt,rlaager/libvirt,iam-TJ/libvirt,jeckersb/libvirt,taget/libvirt,jeckersb/libvirt,shugaoye/libvirt,cbosdo/libvirt,nertpinx/libvirt,jardasgit/libvirt,elmarco/libvirt,agx/libvirt,jeckersb/libvirt,crobinso/libvirt,elmarco/libvirt,fabianfreyer/libvirt,emaste/libvirt,emaste/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,siboulet/libvirt-openvz,jeckersb/libvirt,nertpinx/libvirt,siboulet/libvirt-openvz,siboulet/libvirt-openvz,trainstack/libvirt,rlaager/libvirt,andreabolognani/libvirt,agx/libvirt,iam-TJ/libvirt,taget/libvirt,VenkatDatta/libvirt,jeckersb/libvirt,eskultety/libvirt,jeckersb/libvirt,emaste/libvirt,elmarco/libvirt,shugaoye/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,emaste/libvirt,libvirt/libvirt,bjzhang/libvirt,trainstack/libvirt,olafhering/libvirt,trainstack/libvirt,emaste/libvirt,VenkatDatta/libvirt,eskultety/libvirt,rlaager/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,trainstack/libvirt,eskultety/libvirt,rlaager/libvirt