Disable cg in simgrid mode

mpi/examples/Makefile.am

@@ -276,6 +276,7 @@ endif
 # CG example #
 ##############
 
+if !STARPU_SIMGRID
 if !STARPU_NO_BLAS_LIB
 examplebin_PROGRAMS += cg/cg
 starpu_mpi_EXAMPLES += cg/cg
@@ -287,6 +288,7 @@ cg_cg_SOURCES =					\
 cg_cg_LDADD =					\
 	$(STARPU_BLAS_LDFLAGS)
 endif
+endif
 
 ###########################
 # MPI Matrix mult example #