vmware/xorg: Fix SCons build.

Not sure how vmw_screen.c could build at all though...

src/gallium/winsys/drm/vmware/xorg/SConscript

@@ -42,6 +42,8 @@ if env['platform'] == 'linux':
 	])
 
 	sources = [
+		'vmw_ioctl.c',
+		'vmw_screen.c',
 		'vmw_xorg.c',
 	]
 

src/gallium/winsys/drm/vmware/xorg/vmw_screen.c

@@ -33,6 +33,8 @@
 #include "vmw_hook.h"
 #include "vmw_driver.h"
 
+#include "cursorstr.h"
+
 /* modified version of crtc functions */
 xf86CrtcFuncsRec vmw_screen_crtc_funcs;