ceilometer compute agent not started correctly

command isn't properly parsed after switch to run_process. this
patch corrects the regression

Change-Id: Ib28d4bbf6f150854fc5aa04e3fa4eed92005ce19
Closes-Bug: #1370673
diff --git a/lib/ceilometer b/lib/ceilometer
index a71643a..0449254 100644
--- a/lib/ceilometer
+++ b/lib/ceilometer
@@ -232,7 +232,7 @@
     # Start the compute agent last to allow time for the collector to
     # fully wake up and connect to the message bus. See bug #1355809
     if [[ "$VIRT_DRIVER" = 'libvirt' ]]; then
-        run_process ceilometer-acompute "sg $LIBVIRT_GROUP 'ceilometer-agent-compute --config-file $CEILOMETER_CONF'"
+        run_process ceilometer-acompute "ceilometer-agent-compute --config-file $CEILOMETER_CONF" $LIBVIRT_GROUP
     fi
     if [[ "$VIRT_DRIVER" = 'vsphere' ]]; then
         run_process ceilometer-acompute "ceilometer-agent-compute --config-file $CEILOMETER_CONF"