Fix logic for ipflush_onchange and restart_on_ipflush

Old logic for ipflush_onchange and restart_on_ipflush restored
for backward compatibility according readme and name semantics.

New pillar option introduced: ifdown_before_changes
New logic for PROD-22473 bug wraped in it
It should be disable in devcloud deployment due to
ifdown will not be executed correctly while interface configuration
is missing in /etc/network/interfaces, until configuration state happens

This commit is squash of 3 following commits:
I4397e9e82f8d4114ced50ff253679a8f27762c17
I8f07c79e2e48e032f41efa52a14e4a4e60137abd
Ib3263accde3d902fec98bd8676db29ff2812e7e2

Closes-Bug: PROD-22473
Closes-Bug: PROD-28414
Related prod: PROD-28458 (PROD:28458)

Change-Id: Ib3263accde3d902fec98bd8676db29ff2812e7e2
diff --git a/linux/network/interface.sls b/linux/network/interface.sls
index 2cfdb3b..326dee4 100644
--- a/linux/network/interface.sls
+++ b/linux/network/interface.sls
@@ -389,31 +389,49 @@
 {%- endif %}
 
 {%- if interface.type in ('eth','ovs_port') %}
-{%- if interface.get('ipflush_onchange', False) %}
 
+  {%- if interface.get('ifdown_before_changes', False) %}
+linux_interface_down_before_change_{{ interface_name }}:
+  cmd.run:
+  - name: ifdown {{ interface_name }}
+  - prereq:
+    {%- if interface.type == 'eth' %}
+    - network: linux_interface_{{ interface_name }}
+    {%- else %}
+    - file: ovs_port_{{ interface_name }}
+    {%- endif %}
+
+linux_interface_up_after_change_{{ interface_name }}:
+  cmd.run:
+  - name: ifup {{ interface_name }}
+  - onchanges:
+    {%- if interface.type == 'eth' %}
+    - network: linux_interface_{{ interface_name }}
+    {%- else %}
+    - file: ovs_port_{{ interface_name }}
+    {%- endif %}
+  {%- endif %}
+
+  {%- if interface.get('ipflush_onchange', False) %}
 linux_interface_ipflush_onchange_{{ interface_name }}:
   cmd.run:
   - name: "/sbin/ip address flush dev {{ interface_name }}"
-{%- if interface.type == 'eth' %}
+    {%- if interface.type == 'eth' %}
   - onchanges:
     - network: linux_interface_{{ interface_name }}
-{%- elif interface.type == 'ovs_port' %}
+    {%- elif interface.type == 'ovs_port' %}
   - onchanges:
     - file: ovs_port_{{ interface_name }}
-{%- endif %}
+    {%- endif %}
 
-{%- if interface.get('restart_on_ipflush', False) %}
-
+    {%- if interface.get('restart_on_ipflush', False) %}
 linux_interface_restart_on_ipflush_{{ interface_name }}:
   cmd.run:
   - name: "ifdown {{ interface_name }}; ifup {{ interface_name }};"
   - onchanges:
     - cmd: linux_interface_ipflush_onchange_{{ interface_name }}
-
-{%- endif %}
-
-{%- endif %}
-
+    {%- endif %}
+  {%- endif %}
 {%- endif %}
 
 {%- endfor %}