command: Move environ-adding code to common function virCommandAddEnv.
command: Move environ-adding code to common function virCommandAddEnv.

This is just code motion.  The semantics of the code should be
identical after this change.

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