core/trivial: replace "XXX" markers with "TODO"

"XXX" is used for tagging parts of code that still need work before
merging a patch. If you want to highlight/mark a comment which is merged
use either "TODO" or "FIXME".

Of course, even "TODO" and "FIXME" should be avoided in favor of just
doing/fixing it. Such things tend to never be done/fixed.

po/zh_CN.po

@@ -3431,8 +3431,8 @@ msgstr "NetworkManaer 未运行。"
 msgid "NetworkManager permissions"
 msgstr "网络管理器权限"
 
-# XXX: 这里考虑一下要不要翻译
-# XXX: Should we translate this?
+# Question: 这里考虑一下要不要翻译
+# Question: Should we translate this?
 #: ../clients/cli/general.c:567
 #, c-format
 msgid "Error: 'general permissions': %s"

src/devices/ovs/nm-ovsdb.c

@@ -1558,7 +1558,7 @@ ovsdb_try_connect (NMOvsdb *self)
 	if (priv->client)
 		return;
 
-	/* XXX: This should probably be made configurable via NetworkManager.conf */
+	/* TODO: This should probably be made configurable via NetworkManager.conf */
 	addr = g_unix_socket_address_new (RUNSTATEDIR "/openvswitch/db.sock");
 
 	priv->client = g_socket_client_new ();

src/nm-policy.c

@@ -2084,7 +2084,7 @@ device_removed (NMManager *manager, NMDevice *device, gpointer user_data)
 	NMPolicy *self = _PRIV_TO_SELF (priv);
 	ActivateData *data;
 
-	/* XXX is this needed? The delegations are cleaned up
+	/* TODO: is this needed? The delegations are cleaned up
 	 * on transition to deactivated too. */
 	ip6_remove_device_prefix_delegations (self, device);
 

src/settings/plugins/ifcfg-rh/tests/network-scripts/ifcfg-test-write-unknown-1

@@ -3,6 +3,6 @@ FOO='val
 wrong line
   F2=b
   F3='b
-XXX=adf'
-  XXX2=val2
+XXA=adf'
+  XXA2=val2
 '

src/settings/plugins/ifcfg-rh/tests/network-scripts/ifcfg-test-write-unknown-1.expected

@@ -6,7 +6,7 @@ bar=
   F2=b
 F3=
 #NM:   F3='b
-XXX=
-#NM: XXX=adf'
-  XXX2=val2
+XXA=
+#NM: XXA=adf'
+  XXA2=val2
 #NM: '