update PV versions for libosmocore, libosmo-sccp and openggsn

As we're building git master, we need to make sure PV is not lagging
behind.  I wish there was some OE magic by which it could discover
PV from the source it builds.

Change-Id: Ib45238e95156f215412d51d975b1acb33633a3e1
diff --git a/recipes-osmocom/libosmo-sccp/libosmo-sccp_git.bb b/recipes-osmocom/libosmo-sccp/libosmo-sccp_git.bb
index 3d55f69..7ec2224 100644
--- a/recipes-osmocom/libosmo-sccp/libosmo-sccp_git.bb
+++ b/recipes-osmocom/libosmo-sccp/libosmo-sccp_git.bb
@@ -3,6 +3,7 @@
 S = "${WORKDIR}/git"
 SRCREV = "54fa75b85c91bb4bb79960942f63968f6423f6a5"
 SRC_URI = "git://git.osmocom.org/libosmo-sccp.git;protocol=git"
+PV = "0.7.0+gitr${SRCPV}"
 PR = "${INC_PR}.0"
 
 # we require the tests to link to the static libosmo-sigtran library to