test-suite: update superlu_dist builds for 6.x version which now require C++ linkage
@@ -10,6 +10,8 @@ check_PROGRAMS += superlu_mod
superlu_mod_SOURCES = superlu_mod.f90
superlu_mod_FCFLAGS = -c
+LIBS = -lstdc++ -lmpi_cxx
+
check_PROGRAMS += pddrive
pddrive_SOURCES = pddrive.c dcreate_matrix.c
