Consistently return 0 on success, -1 on failure in bridge_driver.c
Consistently return 0 on success, -1 on failure in bridge_driver.c

Some functions in this file were returning 1 on success and 0 on
failure, and others were returning 0 on success and -1 on
failure. Switch them all to return the libvirt-preferred 0/-1.

jeckersb/libvirt,datto/libvirt,novel/fbsd-libvirt,jeckersb/libvirt,dumbbell/libvirt,wiedi/libvirt,taget/libvirt,elmarco/libvirt,shugaoye/libvirt,novel/fbsd-libvirt,andreabolognani/libvirt,leilihh/libvirt,eskultety/libvirt,dumbbell/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,novel/fbsd-libvirt,emaste/libvirt,emaste/libvirt,rmarwaha/libvirt,taget/libvirt,rlaager/libvirt,dumbbell/libvirt,crobinso/libvirt,warewolf/libvirt,soulxu/libvirt-xuhj,wiedi/libvirt,libvirt/libvirt,crobinso/libvirt,jfehlig/libvirt,andreabolognani/libvirt,olafhering/libvirt,jardasgit/libvirt,novel/fbsd-libvirt,iam-TJ/libvirt,iam-TJ/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,usc-isi/libvirt,leilihh/libvirt,elmarco/libvirt,rmarwaha/libvirt,eskultety/libvirt,foomango/libvirt,rmarwaha/libvirt1,novel/fbsd-libvirt,foomango/libvirt,leilihh/libvirt,zippy2/libvirt,dumbbell/libvirt,siboulet/libvirt-openvz,kantai/libvirt-vfork,iam-TJ/libvirt,taget/libvirt,danwent/libvirt-ovs,wiedi/libvirt,cbosdo/libvirt,iam-TJ/libvirt,kantai/libvirt-vfork,jfehlig/libvirt,zhlcindy/libvirt-1.1.4-maintain,rlaager/libvirt,fabianfreyer/libvirt,elmarco/libvirt,novel/fbsd-libvirt,novel/fbsd-libvirt,usc-isi/libvirt,rbu/libvirt,danwent/libvirt-ovs,datto/libvirt,leilihh/libvirt,dumbbell/libvirt,kantai/libvirt-vfork,sshah-solarflare/Libvirt-PCI-passthrough-,usc-isi/libvirt,VenkatDatta/libvirt,jfehlig/libvirt,zhlcindy/libvirt-1.1.4-maintain,soulxu/libvirt-xuhj,eskultety/libvirt,novel/fbsd-libvirt,siboulet/libvirt-openvz,andreabolognani/libvirt,soulxu/libvirt-xuhj,rmarwaha/libvirt1,siboulet/libvirt-openvz,nertpinx/libvirt,taget/libvirt,novel/fbsd-libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,rmarwaha/libvirt1,warewolf/libvirt,usc-isi/libvirt,wiedi/libvirt,bjzhang/libvirt,dumbbell/libvirt,shugaoye/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,emaste/libvirt,jeckersb/libvirt,leilihh/libvirt,trainstack/libvirt,usc-isi/libvirt,trainstack/libvirt,jeckersb/libvirt,rmarwaha/libvirt,rlaager/libvirt,rmarwaha/libvirt,libvirt/libvirt,zippy2/libvirt,siboulet/libvirt-openvz,jeckersb/libvirt,VenkatDatta/libvirt,agx/libvirt,cbosdo/libvirt,warewolf/libvirt,rmarwaha/libvirt1,trainstack/libvirt,zippy2/libvirt,libvirt/libvirt,olafhering/libvirt,trainstack/libvirt,warewolf/libvirt,crobinso/libvirt,datto/libvirt,jeckersb/libvirt,wiedi/libvirt,olafhering/libvirt,agx/libvirt,cbosdo/libvirt,emaste/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,foomango/libvirt,siboulet/libvirt-openvz,bjzhang/libvirt,bjzhang/libvirt,emaste/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,danwent/libvirt-ovs,jardasgit/libvirt,emaste/libvirt,warewolf/libvirt,jardasgit/libvirt,rlaager/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,taget/libvirt,iam-TJ/libvirt,rmarwaha/libvirt1,nertpinx/libvirt,andreabolognani/libvirt,agx/libvirt,trainstack/libvirt,shugaoye/libvirt,elmarco/libvirt,soulxu/libvirt-xuhj,leilihh/libvirt,warewolf/libvirt,elmarco/libvirt,fabianfreyer/libvirt,kantai/libvirt-vfork,agx/libvirt,trainstack/libvirt,zhlcindy/libvirt-1.1.4-maintain,eskultety/libvirt,rbu/libvirt,fabianfreyer/libvirt,kantai/libvirt-vfork,trainstack/libvirt,rbu/libvirt,bjzhang/libvirt,nertpinx/libvirt,bjzhang/libvirt,eskultety/libvirt,rmarwaha/libvirt,rmarwaha/libvirt1,andreabolognani/libvirt,iam-TJ/libvirt,fabianfreyer/libvirt,shugaoye/libvirt,agx/libvirt,jfehlig/libvirt,zhlcindy/libvirt-1.1.4-maintain,emaste/libvirt,datto/libvirt,warewolf/libvirt,datto/libvirt,crobinso/libvirt,cbosdo/libvirt,wiedi/libvirt,zhlcindy/libvirt-1.1.4-maintain,rbu/libvirt,iam-TJ/libvirt,foomango/libvirt,danwent/libvirt-ovs,zippy2/libvirt,soulxu/libvirt-xuhj,jeckersb/libvirt,foomango/libvirt,libvirt/libvirt,olafhering/libvirt,rbu/libvirt,jardasgit/libvirt,rmarwaha/libvirt,rlaager/libvirt,cbosdo/libvirt,shugaoye/libvirt,nertpinx/libvirt,wiedi/libvirt,danwent/libvirt-ovs