dsextras.py: use distutils.spawn.find_executable for have_pkgconfig()
dsextras.py: use distutils.spawn.find_executable for have_pkgconfig()

nzjrs/pygobject,davibe/pygobject,thiblahute/pygobject,nzjrs/pygobject,alexef/pygobject,GNOME/pygobject,choeger/pygobject-cmake,davidmalcolm/pygobject,pexip/pygobject,GNOME/pygobject,Distrotech/pygobject,MathieuDuponchelle/pygobject,MathieuDuponchelle/pygobject,alexef/pygobject,sfeltman/pygobject,jdahlin/pygobject,Distrotech/pygobject,sfeltman/pygobject,davibe/pygobject,davibe/pygobject,davidmalcolm/pygobject,davibe/pygobject,jdahlin/pygobject,choeger/pygobject-cmake,Distrotech/pygobject,Distrotech/pygobject,MathieuDuponchelle/pygobject,alexef/pygobject,thiblahute/pygobject,thiblahute/pygobject,jdahlin/pygobject,choeger/pygobject-cmake,GNOME/pygobject,nzjrs/pygobject,pexip/pygobject,sfeltman/pygobject,davidmalcolm/pygobject,pexip/pygobject