osmocom: Use CONFFILES for cfg files

Change-Id: I4a4c7d4a5e3e58c413c82b75f442ae9321d64998
diff --git a/recipes-osmocom/osmo-msc/osmo-msc.inc b/recipes-osmocom/osmo-msc/osmo-msc.inc
index 9be747d..82a51b1 100644
--- a/recipes-osmocom/osmo-msc/osmo-msc.inc
+++ b/recipes-osmocom/osmo-msc/osmo-msc.inc
@@ -5,7 +5,7 @@
 
 DEPENDS = "libdbi libosmocore libosmo-abis libosmo-sccp libosmo-netif osmo-mgw"
 
-INC_PR="r2.${META_TELEPHONY_OSMO_INC}"
+INC_PR="r3.${META_TELEPHONY_OSMO_INC}"
 
 inherit autotools pkgconfig systemd
 
@@ -28,3 +28,4 @@
 }
 
 SYSTEMD_SERVICE_${PN} = "${PN}.service"
+CONFFILES_osmo-msc = "${sysconfdir}/osmocom/osmo-msc.cfg"