message: Update make logic for Windows dll check
diff: @@ -56,7 +56,7 @@ endif
  $(LINK.cpp) $(subst \,/,$*.o) $(CMDSTAN_MAIN_O) $(LDLIBS) $(LIBSUNDIALS) $(MPI_TARGETS) $(TBB_TARGETS) $(subst \,/,$(OUTPUT_OPTION))
  $(RM) $(subst \,/,$*).o
  ifeq ($(OS),Windows_NT)
  -ifneq ($(notdir $(shell where tbb.dll)),tbb.dll)
  +ifneq (,$(findstring tbb.dll, $(notdir $(shell where tbb.dll))))
  @echo 'Intel TBB is not in PATH.'
  @echo 'Consider calling '
  @echo '$(HELP_MAKE) install-tbb'
  