Drop sysmocom-bsc-image.bb

It's not actually being built by any job, and its contents are anyway
wrong since it basically pulls in the same as the sysmocom-nitb-image.

Initially it made sense to have these 2 images because we either
connected the BTS to osmo-bsc or osmo-nitb. This is no longer the case
since we deprecated osmo-nitb, and now it always connects to osmo-bsc.

The initiall idea after osmo-nitb split was to have a sysmo-bsc-image
containing only osmo-bsc, and then a sysmocom-nitb-image superseeding
it by installing all other core network components such as hlr, msc, etc.

Since there's no real need for that now, and in any case we can just
duse the nitb one and disable the extra services, let's drop the bsc
one.

recipes-apps/images/sysmocom-bsc-image.bb

@@ -1,14 +0,0 @@
-require sysmocom-image.inc
-
-IMAGE_INSTALL_append = " task-sysmocom "
-
-# This variant of the image will run osmo-bts and osmo-bsc
-activate_bsc() {
-	echo "NO_START=0" > ${IMAGE_ROOTFS}/etc/default/osmo-bsc
-}
-
-activate_systemd_bsc() {
-        ln -sf ${systemd_system_unitdir}/osmo-bsc.service ${IMAGE_ROOTFS}/etc/systemd/system/multi-user.target.wants/
-}
-
-IMAGE_PREPROCESS_COMMAND += "${@bb.utils.contains('DISTRO_FEATURES','systemd','activate_systemd_bsc','activate_bsc',d)}; "