llvmpipe: Add missing include path.

The abscense was being masked previously.

src/gallium/drivers/llvmpipe/SConscript

@@ -9,6 +9,8 @@ if not env.has_key('LLVM_VERSION'):
 
 env.Tool('udis86')
 
+env.Append(CPPPATH = ['.'])
+
 env.CodeGenerate(
 	target = 'lp_tile_soa.c',
 	script = 'lp_tile_soa.py',