Windows package: fix race condition when extracting MSYS2 archives

Those archives contain 3 hidden files, which always have the same name. This
can make the parallel build fail when several packages are unpacked at the same
time. Hence, we just skip these files when unpacking.

.gitignore

@@ -123,9 +123,6 @@ doc/internals/ltxpng
 # Windows
 !/windows/Makefile
 !/windows/deps/Makefile
-windows/deps/.BUILDINFO
-windows/deps/.MTREE
-windows/deps/.PKGINFO
 windows/deps/lib32/
 windows/deps/lib64/
 windows/deps/lib32-msys2/

windows/deps/Makefile

@@ -220,26 +220,28 @@ clean-matlab:
 
 msys2: lib32-msys2 lib64-msys2 mingw32 mingw64
 
+MSYS2_EXCLUDES := --exclude .MTREE --exclude .BUILDINFO --exclude .PKGINFO
+
 lib32-msys2: tarballs/mingw-w64-i686-boost-$(MINGW32_BOOST_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-gsl-$(MINGW32_GSL_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-openblas-$(MINGW32_OPENBLAS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-matio-$(MINGW32_MATIO_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-zlib-$(MINGW32_ZLIB_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-hdf5-$(MINGW32_HDF5_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-szip-$(MINGW32_SZIP_VERSION)-any.pkg.tar.xz
 	rm -rf $@
 	mkdir $@
-	for f in $^; do tar xf $$f --directory $@ --strip-components 1; done
+	for f in $^; do tar xf $$f --directory $@ --strip-components 1 $(MSYS2_EXCLUDES); done
 	touch $@
 
 lib64-msys2: tarballs/mingw-w64-x86_64-boost-$(MINGW64_BOOST_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-gsl-$(MINGW64_GSL_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-openblas-$(MINGW64_OPENBLAS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-matio-$(MINGW64_MATIO_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-zlib-$(MINGW64_ZLIB_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-hdf5-$(MINGW64_HDF5_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-szip-$(MINGW64_SZIP_VERSION)-any.pkg.tar.xz
 	rm -rf $@
 	mkdir $@
-	for f in $^; do tar xf $$f --directory $@ --strip-components 1; done
+	for f in $^; do tar xf $$f --directory $@ --strip-components 1 $(MSYS2_EXCLUDES); done
 	touch $@
 
 mingw32: tarballs/mingw-w64-i686-gcc-$(MINGW32_GCC_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-gmp-$(MINGW32_GMP_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-binutils-$(MINGW32_BINUTILS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-headers-git-$(MINGW32_HEADERS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-crt-git-$(MINGW32_CRT_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-winpthreads-git-$(MINGW32_WINPTHREADS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-i686-libwinpthread-git-$(MINGW32_LIBWINPTHREAD_VERSION)-any.pkg.tar.xz
 	rm -rf $@
-	for f in $^; do tar xf $$f; done
+	for f in $^; do tar xf $$f $(MSYS2_EXCLUDES); done
 	touch $@
 
 mingw64: tarballs/mingw-w64-x86_64-gcc-$(MINGW64_GCC_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-gmp-$(MINGW64_GMP_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-binutils-$(MINGW64_BINUTILS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-headers-git-$(MINGW64_HEADERS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-crt-git-$(MINGW64_CRT_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-winpthreads-git-$(MINGW64_WINPTHREADS_VERSION)-any.pkg.tar.xz tarballs/mingw-w64-x86_64-libwinpthread-git-$(MINGW64_LIBWINPTHREAD_VERSION)-any.pkg.tar.xz
 	rm -rf $@
-	for f in $^; do tar xf $$f; done
+	for f in $^; do tar xf $$f $(MSYS2_EXCLUDES); done
 	touch $@
 
 tarballs/mingw-w64-i686-%-any.pkg.tar.xz: