mesa3d: don't depend on the X server

There's no particular reason why you shouldn't be able to build mesa
without the X server (E.G. for remote X), so remove it.

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

package/x11r7/mesa3d/Config.in

@@ -7,7 +7,6 @@ config BR2_PACKAGE_MESA3D
 	select BR2_PACKAGE_XPROTO_DRI2PROTO
 	select BR2_PACKAGE_LIBDRM
 	select BR2_PACKAGE_EXPAT
-	depends on BR2_PACKAGE_XSERVER_XORG_SERVER
 	depends on BR2_PACKAGE_XSERVER_xorg
 	depends on BR2_INSTALL_LIBSTDCPP
 	help