packaging: Always use xzcat(1) to decompress xz archive

Do not rely on tar's behaviour. It was already done everywhere except in
those three places.

Author: dumbbell

packaging/debs/Debian/Makefile

@@ -32,7 +32,7 @@ all: package
 
 package: clean
 	cp -a $(SOURCE_DIST_FILE) $(DEBIAN_ORIG_TARBALL)
-	tar -Jxf $(DEBIAN_ORIG_TARBALL)
+	xzcat $(DEBIAN_ORIG_TARBALL) | tar -xf -
 	cp -a debian $(UNPACKED_DIR)
 	rsync -a \
 		--exclude '.sw?' --exclude '.*.sw?' \

packaging/generic-unix/Makefile

@@ -25,7 +25,7 @@ all: dist
 	@:
 
 dist:
-	tar -Jxf $(SOURCE_DIST_FILE)
+	xzcat $(SOURCE_DIST_FILE) | tar -xf -
 
 # web-manpages are not used by generic-unix but by `make release` in the.
 # Umbrella. Those manpages are copied to www.rabbitmq.com

packaging/windows/Makefile

@@ -25,7 +25,7 @@ all: dist
 	@:
 
 dist:
-	tar -Jxf $(SOURCE_DIST_FILE)
+	xzcat $(SOURCE_DIST_FILE) | tar -xf -
 	$(MAKE) -C $(SOURCE_DIR) install-windows \
 		DESTDIR=$(abspath $(TARGET_DIR)) \
 		WINDOWS_PREFIX=