xosd: call vlc_xlib_init first

See: https://bugs.gentoo.org/show_bug.cgi?id=393439Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>
(cherry picked from commit 9b40c48c)

modules/notify/xosd.c

@@ -34,6 +34,7 @@
 #include <vlc_playlist.h>
 #include <vlc_input.h>
 #include <vlc_interface.h>
+#include <vlc_xlib.h>
 
 #include <xosd.h>
 
@@ -109,6 +110,9 @@ static int Open( vlc_object_t *p_this )
     xosd *p_osd;
     char *psz_font, *psz_colour;
 
+    if (!vlc_xlib_init(p_this))
+        return VLC_EGENERIC;
+
     if( getenv( "DISPLAY" ) == NULL )
     {
         msg_Err( p_intf, "no display, please set the DISPLAY variable" );