misc: Modernize and call it packagegroup-

The notion of task- has been deprecated a long time ago. Call
it packagegroup now and for "packagegroup-osmocom" provide the
compability. This has not been compile tested.

The edison build will require a bbappend to provide packagegroup
now but I will do this once I need to build for Edison again.
diff --git a/recipes-telephony/tasks/task-telephony-all.bb b/recipes-telephony/tasks/task-telephony-all.bb
index 284d669..cc1ca0b 100644
--- a/recipes-telephony/tasks/task-telephony-all.bb
+++ b/recipes-telephony/tasks/task-telephony-all.bb
@@ -3,14 +3,14 @@
 LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420 \
                     file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
 ALLOW_EMPTY_${PN} = "1"
-PR = "r3"
+PR = "r4"
 
 DEPENDS = "\
         libosmo-abis \
         libosmo-sccp \
         libosmocore \
         openbsc \
-        task-osmocom \
+        packagegroup-osmocom \
         openggsn \
         misdn-utils \
         dahdi-linux \