xserver-xorg: select mesa3d in kconfig

xserver-xorg depends on mesa3d, so select it in kconfig as well.

package/x11r7/mesa3d/Config.in

@@ -1,7 +1,7 @@
 config BR2_PACKAGE_MESA3D
 	bool "Mesa 3D Graphics Library"
 	select BR2_PACKAGE_XPROTO_GLPROTO
-	select BR2_PACKAGE_XSERVER_XORG_SERVER
+	depends on BR2_PACKAGE_XSERVER_XORG_SERVER
 	help
 	  Mesa 3D, an open-source implementation of the OpenGL specification.
 

package/x11r7/xserver_xorg-server/Config.in

@@ -52,6 +52,7 @@ config BR2_PACKAGE_XSERVER_XORG_SERVER
 	select BR2_PACKAGE_XPROTO_XPROTO
 	select BR2_PACKAGE_PIXMAN
 	select BR2_PACKAGE_XLIB_LIBXSCRNSAVER
+	select BR2_PACKAGE_MESA3D if BR2_PACKAGE_XSERVER_xorg
 	help
 	  xorg-server 1.4
 	  No description available