This fixes a bug introduced inwip-gnome3.36
362bcdb1b0whereby the VM image would no longer contain /etc/config.scm, contrary to what the manual says. Reported by dbdude on #guix. * Makefile.am (release): Pass '--save-provenance' to 'guix system vm-image'. * doc/guix.texi (Running Guix in a VM): Adjust file name accordingly.