Pass custom args to create_port through create_server

Allow consumers of create_server to pass custom arguments to
create_port method which is called from create_server one.

Fix namestart var usage in create_port - as the name of the var
suggests, it should be used to generate a name from. Therefore
the patch also adds rand_name call which we accidentaly removed
recently.

Implements: blueprint tempest-scenario-manager-stable
Change-Id: I724e0f37d4381a493217a077492046f7a4b0a2a2
1 file changed