Remove calculation for NeutronDhcpAgentsPerNetwork

This patch removes the calculation that set the
NeutronDhcpAgentsPerNetwork configuration based on the number of
"controllers" being deployed. With composable roles, this is incorrect
and the default, if required, should be determined by the number of
neutron dhcp agent services being deployed - not a role count.

Closes-Bug: #1632721
Depends-On: I06628764c4769d91bbc42efe1c722702d6574d02
Change-Id: If202a8255f8ad9f662f0d66a5f630f1b7ae60a26
(cherry picked from commit 1051880e92)
(cherry picked from commit 4a5fb3810e)

releasenotes/notes/remove-neutron-dhcp-agents-per-network-1f34e5deeba71cda.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Removed setting NeutronDhcpAgentsPerNetwork based on controller count.
+    If not overridden by the user, it should be calculated based on the
+    number of neutron DHCP agents that are actually deployed.

tripleoclient/tests/v1/overcloud_deploy/test_overcloud_deploy.py

@@ -179,7 +179,6 @@ class TestDeployOvercloud(fakes.TestDeployOvercloud):
             'ManilaPassword': 'password',
             'MistralPassword': 'password',
             'MysqlClustercheckPassword': 'password',
-            'NeutronDhcpAgentsPerNetwork': 1,
             'NeutronDnsmasqOptions': 'dhcp-option-force=26,1400',
             'NeutronFlatNetworks': 'datacentre',
             'NeutronMetadataProxySharedSecret': 'password',
@@ -355,7 +354,6 @@ class TestDeployOvercloud(fakes.TestDeployOvercloud):
             'ManilaPassword': 'password',
             'MistralPassword': 'password',
             'MysqlClustercheckPassword': 'password',
-            'NeutronDhcpAgentsPerNetwork': 1,
             'NeutronDnsmasqOptions': 'dhcp-option-force=26,1400',
             'NeutronFlatNetworks': 'datacentre',
             'NeutronNetworkType': 'gre',
@@ -1427,7 +1425,6 @@ class TestDeployOvercloud(fakes.TestDeployOvercloud):
             'ManilaPassword': 'password',
             'MistralPassword': 'password',
             'MysqlClustercheckPassword': 'password',
-            'NeutronDhcpAgentsPerNetwork': 3,
             'NeutronDnsmasqOptions': 'dhcp-option-force=26,1400',
             'NeutronFlatNetworks': 'datacentre',
             'NeutronNetworkType': 'gre',

tripleoclient/v1/overcloud_deploy.py

@@ -116,15 +116,6 @@ class DeployOvercloud(command.Command):
                 else:
                     parameters[param] = getattr(args, arg)
 
-        # Scaling needs extra parameters
-        number_controllers = int(parameters.get('ControllerCount', 0))
-        dhcp_agents_per_network = (min(number_controllers, 3) if
-                                   number_controllers else 1)
-
-        parameters.update({
-            'NeutronDhcpAgentsPerNetwork': dhcp_agents_per_network,
-        })
-
         return parameters
 
     def _create_registration_env(self, args):