Use dynamic import for conditional task imports

When task import condition is false, we need to use include instead
of import, since this allows not running through all tasks and
reduce amount of skipped tasks for such deployments.

Change-Id: I4b51290b94b5b4b54b111d197688f65129a4f5ad

tasks/main.yml

@@ -77,11 +77,15 @@
     - common-mq
     - octavia-config
 
-- import_tasks: octavia_certs.yml
+- include_tasks: octavia_certs.yml
+  args:
+    apply:
+      tags:
+        - octavia-config
   run_once: true
   when: octavia_generate_certs | bool
   tags:
-    - octavia-config
+    - always
 
 - name: Gather variables for installation method
   include_vars: "{{ octavia_install_method }}_install.yml"
@@ -97,9 +101,13 @@
     - octavia-install
 
 - include_tasks: octavia_certs_distribute.yml
+  args:
+    apply:
+      tags:
+        - octavia-config
   when: octavia_generate_certs | bool
   tags:
-    - octavia-config
+    - always
 
 - name: Import uwsgi role
   import_role:
@@ -165,14 +173,18 @@
   tags:
     - octavia-install
 
-- import_tasks: octavia_mgmt_network.yml
+- include_tasks: octavia_mgmt_network.yml
+  args:
+    apply:
+      tags:
+        - octavia-install
+        - octavia-config
   when:
     - octavia_neutron_management_network_uuid is not defined
     - octavia_neutron_management_network_name is defined
     - _octavia_is_first_play_host
   tags:
-    - octavia-install
-    - octavia-config
+    - always
 
 - import_tasks: octavia_security_group.yml
   when:
@@ -181,18 +193,26 @@
     - octavia-install
 
 - include_tasks: octavia_keypair.yml
+  args:
+    apply:
+      tags:
+        - octavia-config
   when:
     - _octavia_is_first_play_host
   tags:
-    - octavia-config
+    - always
 
-- import_tasks: octavia_flavor_create.yml
+- include_tasks: octavia_flavor_create.yml
+  args:
+    apply:
+      tags:
+        - octavia-install
+        - octavia-config
   when:
     - _octavia_is_first_play_host
     - octavia_nova_flavor_uuid is not defined
   tags:
-    - octavia-install
-    - octavia-config
+    - always
 
 - import_tasks: octavia_post_install.yml
   tags:
@@ -211,11 +231,16 @@
     - octavia-config
     - octavia-policy-override
 
-- import_tasks: octavia_amp_image.yml
+- include_tasks: octavia_amp_image.yml
+  args:
+    apply:
+      tags:
+        - octavia-config
   when:
     - _octavia_is_first_play_host
+    - octavia_download_artefact | bool
   tags:
-    - octavia-config
+    - always
 
 - name: Flush handlers
   meta: flush_handlers

tasks/octavia_amp_image.yml

@@ -29,8 +29,6 @@
         state: directory
         mode: "0750"
         owner: "{{ octavia_amp_image_path_owner }}"
-      when:
-        - octavia_download_artefact | bool
 
     - name: Download image from artefact server
       get_url:
@@ -39,8 +37,6 @@
       retries: 10
       delay: 10
       register: octavia_download_result
-      when:
-        - octavia_download_artefact | bool
 
     - name: Replace existing image with new one
       when: