Add libwinpthread to runtime dll handling

downloading from opensuse to possibly work around winrpm issues for now
it's likely going to be fragile to use opensuse runtime libs with the
old cygwin toolchain, will have to see

(cherry picked from commit 986c103)
ref #20152

Makefile

@@ -322,6 +322,7 @@ else
 $(eval $(call std_dll,gcc_s_seh-1))
 endif
 $(eval $(call std_dll,ssp-0))
+$(eval $(call std_dll,winpthread-1))
 endif
 define stringreplace
 	$(build_depsbindir)/stringreplace $$(strings -t x - $1 | grep '$2' | awk '{print $$1;}') '$3' 255 "$(call cygpath_w,$1)"
@@ -473,7 +474,7 @@ endif
 
 ifeq ($(OS), WINNT)
 	[ ! -d $(JULIAHOME)/dist-extras ] || ( cd $(JULIAHOME)/dist-extras && \
-		cp 7z.exe 7z.dll libexpat-1.dll zlib1.dll $(BUILDROOT)/julia-$(JULIA_COMMIT)/bin )
+		cp 7z.exe 7z.dll libexpat-1.dll zlib1.dll libgfortran-3.dll libquadmath-0.dll libstdc++-6.dll libgcc_s_s*-1.dll libssp-0.dll libwinpthread-1.dll $(BUILDROOT)/julia-$(JULIA_COMMIT)/bin )
 ifeq ($(USE_GPL_LIBS), 1)
 	[ ! -d $(JULIAHOME)/dist-extras ] || ( cd $(JULIAHOME)/dist-extras && \
 		cp busybox.exe $(BUILDROOT)/julia-$(JULIA_COMMIT)/bin )
@@ -602,7 +603,7 @@ ifneq (,$(filter $(ARCH), i386 i486 i586 i686))
 	$(JLDOWNLOAD) http://downloads.sourceforge.net/sevenzip/7z920.exe && \
 	7z x -y 7z920.exe 7z.exe 7z.dll && \
 	../contrib/windows/winrpm.sh http://download.opensuse.org/repositories/windows:/mingw:/win32/openSUSE_13.2 \
-		"mingw32-libgfortran3 mingw32-libquadmath0 mingw32-libstdc++6 mingw32-libgcc_s_sjlj1 mingw32-libssp0 mingw32-libexpat1 mingw32-zlib1" && \
+		"mingw32-libgfortran3 mingw32-libquadmath0 mingw32-libstdc++6 mingw32-libgcc_s_sjlj1 mingw32-libssp0 mingw32-libwinpthread1 mingw32-libexpat1 mingw32-zlib1" && \
 	cp usr/i686-w64-mingw32/sys-root/mingw/bin/*.dll .
 else ifeq ($(ARCH),x86_64)
 	cd $(JULIAHOME)/dist-extras && \
@@ -611,7 +612,7 @@ else ifeq ($(ARCH),x86_64)
 	mv _7z.dll 7z.dll && \
 	mv _7z.exe 7z.exe && \
 	../contrib/windows/winrpm.sh http://download.opensuse.org/repositories/windows:/mingw:/win64/openSUSE_13.2 \
-		"mingw64-libgfortran3 mingw64-libquadmath0 mingw64-libstdc++6 mingw64-libgcc_s_seh1 mingw64-libssp0 mingw64-libexpat1 mingw64-zlib1" && \
+		"mingw64-libgfortran3 mingw64-libquadmath0 mingw64-libstdc++6 mingw64-libgcc_s_seh1 mingw64-libssp0 mingw64-libwinpthread1 mingw64-libexpat1 mingw64-zlib1" && \
 	cp usr/x86_64-w64-mingw32/sys-root/mingw/bin/*.dll .
 else
 	$(error no win-extras target for ARCH=$(ARCH))