mpi/examples/mpi_lu/pxlu.h: add missing include

mpi/examples/mpi_lu/pxlu.h

@@ -20,6 +20,7 @@
 /* for STARPU_USE_CUDA */
 #include <starpu_config.h>
 #include <starpu.h>
+#include <starpu_cuda.h>
 
 #include <common/blas.h>