[gnome-panel] launcher: fix build warnings

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 4fb91d256c7d4a345efd26ee0ea2db120fc46e5d
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Mon Dec 19 02:12:46 2016 +0200

    launcher: fix build warnings

 gnome-panel/launcher.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gnome-panel/launcher.c b/gnome-panel/launcher.c
index 96d03ac..39c45cd 100644
--- a/gnome-panel/launcher.c
+++ b/gnome-panel/launcher.c
@@ -1294,8 +1294,8 @@ panel_launcher_set_dnd_enabled (Launcher *launcher,
 
        if (dnd_enabled) {
                static GtkTargetEntry dnd_targets[] = {
-                       { "application/x-panel-icon-internal", 0, TARGET_ICON_INTERNAL },
-                       { "text/uri-list", 0, TARGET_URI_LIST }
+                       { (gchar *) "application/x-panel-icon-internal", 0, TARGET_ICON_INTERNAL },
+                       { (gchar *) "text/uri-list", 0, TARGET_URI_LIST }
                };
 
                gtk_widget_set_has_window (launcher->button, TRUE);