Fixup previous apt_key patch to enable file based modes to work.

packaging/apt_key

@@ -129,9 +129,13 @@ def download_key(module, url):
         module.fail_json(msg="error getting key id from url", traceback=format_exc())
 
 
-def add_key(module, key):
-    cmd = "apt-key add -"
-    (rc, out, err) = module.run_command(cmd, data=key, check_rc=True, binary_data=True)
+def add_key(module, keyfile, data=None):
+    if data is not None:
+        cmd = "apt-key add -"
+        (rc, out, err) = module.run_command(cmd, data=data, check_rc=True, binary_data=True)
+    else:
+        cmd = "apt-key add %s" % (keyfile)
+        (rc, out, err) = module.run_command(cmd, check_rc=True)
     return True
 
 def remove_key(module, key_id):
@@ -156,7 +160,7 @@ def main():
     key_id          = module.params['id']
     url             = module.params['url']
     data            = module.params['data']
-    file            = module.params['file']
+    filename        = module.params['file']
     state           = module.params['state']
     changed         = False
     
@@ -170,14 +174,17 @@ def main():
         if key_id and key_id in keys:
             module.exit_json(changed=False)
         else:
-            if not file and not data:
+            if not filename and not data:
                 data = download_key(module, url)
             if key_id and key_id in keys:
                 module.exit_json(changed=False)
             else:
                 if module.check_mode:
                     module.exit_json(changed=True)
-                add_key(module, (file if file else "-"), data)
+                if filename:
+                    add_key(module, filename)
+                else:
+                    add_key(module, "-", data)
                 changed=False
                 keys2 = all_keys(module)
                 if len(keys) != len(keys2):