MT#55283 actually grant the capabilities

Capabilities listed in the ambient set must also be included in the
bounding set.

Change-Id: I172bd30c9fbe488574e9cc015ba552e805c95fe6
(cherry picked from commit 7200c7af64)

debian/ngcp-rtpengine-daemon.service

@@ -66,6 +66,7 @@ CapabilityBoundingSet=
 
 # Service process does not receive ambient capabilities
 # NOTE: we need caps for running as non-root user
+CapabilityBoundingSet=CAP_NET_ADMIN CAP_SYS_NICE
 AmbientCapabilities=CAP_NET_ADMIN CAP_SYS_NICE
 
 # Service has no access to other software's temporary files