download: create immutable subversion checkout archive

On each generation of the archive check sum will differ, because when
checking out subversion repository, current date is used for directories
creation. Force tar to assign creation date of the last revision for all
items inside archive.

Signed-off-by: Tomasz Maciej Nowak <[email protected]>

include/download.mk

@@ -187,7 +187,7 @@ define DownloadMethod/svn
 		svn export --non-interactive --trust-server-cert -r$(VERSION) $(URL) $(SUBDIR) || \
 		svn export --non-interactive -r$(VERSION) $(URL) $(SUBDIR) ) && \
 		echo "Packing checkout..." && \
-		export TAR_TIMESTAMP="" && \
+		export TAR_TIMESTAMP="`svn info -r$(VERSION) --show-item last-changed-date $(URL)`" && \
 		$(call dl_tar_pack,$(TMP_DIR)/dl/$(FILE),$(SUBDIR)) && \
 		mv $(TMP_DIR)/dl/$(FILE) $(DL_DIR)/ && \
 		rm -rf $(SUBDIR); \