util: Do not keep PCI device config file open
util: Do not keep PCI device config file open

Directly open and close PCI config file in the APIs that need it rather
than keeping the file open for the whole life of PCI device structure.

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