logo: missing initializer

(cherry picked from commit 560374a8a12a22ea26cad63ceb150c76dcc70f98)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/video_filter/logo.c

@@ -276,6 +276,7 @@ static int OpenCommon( vlc_object_t *p_this, bool b_sub )
     p_sys->i_pos = var_CreateGetIntegerCommand( p_filter, "logo-position" );
     p_sys->i_pos_x = var_CreateGetIntegerCommand( p_filter, "logo-x" );
     p_sys->i_pos_y = var_CreateGetIntegerCommand( p_filter, "logo-y" );
+    p_sys->b_absolute = (p_sys->i_pos < 0);
 
     /* Ignore aligment if a position is given for video filter */
     if( !b_sub && p_sys->i_pos_x >= 0 && p_sys->i_pos_y >= 0 )