winbuild: In MakefileBuild.vc fix typo DISTDIR->DIRDIST

Change requirement from $(DISTDIR) to $(DIRDIST)

closes #2603
diff --git a/winbuild/MakefileBuild.vc b/winbuild/MakefileBuild.vc
index bf79db3..51ebfb8 100644
--- a/winbuild/MakefileBuild.vc
+++ b/winbuild/MakefileBuild.vc
@@ -502,7 +502,7 @@
 	@-$(ZIP) -9 -q -r ..\$(CONFIG_NAME_LIB).zip .>nul 2<&1

 	@cd $(MAKEDIR)

 

-$(TARGET): $(LIB_OBJS) $(LIB_DIROBJ) $(DISTDIR)

+$(TARGET): $(LIB_OBJS) $(LIB_DIROBJ) $(DIRDIST)

 	@echo Using SSL: $(USE_SSL)

 	@echo Using NGHTTP2: $(USE_NGHTTP2)

 	@echo Using c-ares: $(USE_CARES)