virTestSetEnvPath: Avoid clearing out PATH
virTestSetEnvPath: Avoid clearing out PATH

If the abs_builddir path already is in PATH and it's in the first
position, due to a bug in our code PATH would be cleared out.

Signed-off-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

olafhering/libvirt,andreabolognani/libvirt,eskultety/libvirt,jfehlig/libvirt,eskultety/libvirt,VenkatDatta/libvirt,datto/libvirt,taget/libvirt,olafhering/libvirt,datto/libvirt,fabianfreyer/libvirt,libvirt/libvirt,datto/libvirt,andreabolognani/libvirt,crobinso/libvirt,jardasgit/libvirt,jardasgit/libvirt,zippy2/libvirt,datto/libvirt,andreabolognani/libvirt,nertpinx/libvirt,zippy2/libvirt,nertpinx/libvirt,crobinso/libvirt,libvirt/libvirt,jardasgit/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,zippy2/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,libvirt/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,taget/libvirt,VenkatDatta/libvirt,taget/libvirt,nertpinx/libvirt,crobinso/libvirt,jfehlig/libvirt,taget/libvirt,VenkatDatta/libvirt,zippy2/libvirt,taget/libvirt,eskultety/libvirt,jfehlig/libvirt,eskultety/libvirt,fabianfreyer/libvirt,olafhering/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,libvirt/libvirt,eskultety/libvirt,VenkatDatta/libvirt,jfehlig/libvirt,crobinso/libvirt,andreabolognani/libvirt,olafhering/libvirt,datto/libvirt