overcloud-compute: add linuxptp package for timemaster service

To configure tripleo-timemaster service we need linuxptp
in overcloud image.

tripleo-heat-template and tripleo-ansible patches
[0]: https://review.opendev.org/#/c/748431/
[1]: https://review.opendev.org/#/c/748439/

Change-Id: I228c47ad2c0f0d00a860c97c4f7977e58edab2e3
(cherry picked from commit 19f62a520c)

elements/overcloud-compute/install.d/package-installs-overcloud-compute

@@ -5,4 +5,5 @@ chrony_package
 pacemaker_remote_package
 sasl_scram_package
 tuned_profiles_cpu_partitioning_package
-ndctl_package
+ndctl_package
+linuxptp_package

elements/overcloud-compute/pkg-map

@@ -7,6 +7,7 @@
     "pacemaker_remote_package": "pacemaker-remote",
     "sasl_scram_package": "cyrus-sasl-scram",
     "tuned_profiles_cpu_partitioning_package": "tuned-profiles-cpu-partitioning",
-    "ndctl_package": "ndctl"
+    "ndctl_package": "ndctl",
+    "linuxptp_package": "linuxptp"
   }
 }