sdl: fix X11 dependencies

No need to build the entire X server to build SDL with X11 support.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/sdl/Config.in

@@ -24,5 +24,7 @@ config BR2_PACKAGE_SDL_QTOPIA
 config BR2_PACKAGE_SDL_X11
 	bool "SDL X11 video driver"
 	depends on BR2_PACKAGE_XORG7
+	select BR2_PACKAGE_XLIB_LIBX11
+	select BR2_PACKAGE_XLIB_LIBXEXT
 
 endif

package/sdl/sdl.mk

@@ -32,7 +32,9 @@ endif
 
 ifeq ($(BR2_PACKAGE_SDL_X11),y)
 SDL_CONF_OPT+=--enable-video-x11=yes
-SDL_DEPENDENCIES += xserver_xorg-server
+SDL_DEPENDENCIES += xlib_libX11 xlib_libXext \
+	$(if $(BR2_PACKAGE_XLIB_LIBXRENDER), xlib_libXrender) \
+	$(if $(BR2_PACKAGE_XLIB_LIBXRANDR), xlib_libXrandr)
 else
 SDL_CONF_OPT+=--enable-video-x11=no
 endif