[client] x11/sdl/wayland: implement new minimize (stub for wayland)

This implements the new minimize function introduced in the last commit
for x11 and SDL. Wayland at current is just a stub and needs some
attention.

client/displayservers/Wayland/shell_xdg.c

@@ -146,3 +146,8 @@ bool waylandGetFullscreen(void)
 {
   return wlWm.fullscreen;
 }
+
+void waylandMinimize(void)
+{
+  //FIXME
+}

client/displayservers/Wayland/wayland.c

@@ -177,6 +177,7 @@ struct LG_DisplayServerOps LGDS_Wayland =
   .setWindowSize       = waylandSetWindowSize,
   .setFullscreen       = waylandSetFullscreen,
   .getFullscreen       = waylandGetFullscreen,
+  .minimize            = waylandMinimize,
 
   .cbInit    = waylandCBInit,
   .cbNotice  = waylandCBNotice,

client/displayservers/Wayland/wayland.h

@@ -254,6 +254,7 @@ bool waylandShellInit(const char * title, bool fullscreen, bool maximize, bool b
 void waylandShellAckConfigureIfNeeded(void);
 void waylandSetFullscreen(bool fs);
 bool waylandGetFullscreen(void);
+void waylandMinimize(void);
 
 // window module
 bool waylandWindowInit(const char * title, bool fullscreen, bool maximize, bool borderless);