Allow setting flavor description

This will, like all other options changes, recreate the flavor. This
matches the workflow allowed by the openstacksdk (if description is
not set, it defaults to None).

Change-Id: I3d46a3f527f0632f42f6796c0a2701addebde640

plugins/modules/compute_flavor.py

@@ -13,6 +13,10 @@ description:
    - Add or remove compute flavors from OpenStack.
    - Updating a flavor consists of deleting and (re)creating a flavor.
 options:
+  description:
+    description:
+       - Description of the flavor.
+    type: str
   disk:
     description:
        - Size of local disk, in GB.
@@ -90,6 +94,7 @@ EXAMPLES = '''
     vcpus: 1
     disk: 10
     ephemeral: 10
+    description: "I am flavor mycloud"
 
 - name: Delete tiny flavor
   openstack.cloud.compute_flavor:
@@ -190,6 +195,7 @@ from ansible_collections.openstack.cloud.plugins.module_utils.openstack import O
 
 class ComputeFlavorModule(OpenStackModule):
     argument_spec = dict(
+        description=dict(),
         disk=dict(type='int'),
         ephemeral=dict(type='int'),
         extra_specs=dict(type='dict'),
@@ -278,7 +284,7 @@ class ComputeFlavorModule(OpenStackModule):
         flavor_attributes = dict(
             (k, self.params[k])
             for k in ['ram', 'vcpus', 'disk', 'ephemeral', 'swap',
-                      'rxtx_factor', 'is_public']
+                      'rxtx_factor', 'is_public', 'description']
             if k in self.params and self.params[k] is not None
             and self.params[k] != flavor[k])
 
@@ -290,7 +296,8 @@ class ComputeFlavorModule(OpenStackModule):
     def _create(self):
         kwargs = dict((k, self.params[k])
                       for k in ['name', 'ram', 'vcpus', 'disk', 'ephemeral',
-                                'swap', 'rxtx_factor', 'is_public']
+                                'swap', 'rxtx_factor', 'is_public',
+                                'description']
                       if self.params[k] is not None)
 
         # Keep for backward compatibility