Update submodules: plugins (new commits)

plugins:
    d98a54b Chris Smith <chris@dmdirc.com>
            Tidy up icky method.

            Gerrit: http://gerrit.dmdirc.com/3992

Change-Id: I8ac5dcea389e5b581d83dcd6d06446af98b40065

modules/plugins

@@ -1 +1 @@
-Subproject commit 4fe44ffe14bc960c44c396aa372d8dbf5e149480
+Subproject commit d98a54ba5a79738b832a801c6833e08bba5db9b4