Remove all remaining uses of sysconfig.sh

package/gluon-autoupdater/Makefile

package/gluon-core/Makefile

...n-core/files/lib/gluon/upgrade/core/initial/001-sysconfig

...re/files/lib/gluon/upgrade/core/initial/011-gluon-network

...-legacy/files/lib/gluon/upgrade/core/legacy/001-sysconfig

...acy/files/lib/gluon/upgrade/core/legacy/011-gluon-network

.../files/lib/gluon/upgrade/mesh-batman-adv/initial/010-mesh

package/gluon-setup-mode/Makefile

package/gluon-setup-mode/files/etc/init.d/gluon-setup-mode

package/gluon-status-page/Makefile