Use 4 cores per MPI slaves when checking

starpu.mk

@@ -16,7 +16,7 @@
 
 if STARPU_USE_MPI_MASTER_SLAVE
 MPI_LAUNCHER 			= $(MPIEXEC)  $(MPIEXEC_ARGS) -np 4
-MPI_RUN_ARGS			= STARPU_WORKERS_NOBIND=1 STARPU_NCPU=4
+MPI_RUN_ARGS			= STARPU_WORKERS_NOBIND=1 STARPU_NCPU=4 STARPU_NMPIMSTHREADS=4
 endif
 
 showcheck: