patch: Change to xz compressed tarball.

Signed-off-by: Ian Leonard <antonlacon@gmail.com>

devel/patch/Makefile

 PKG_VERSION:=2.7.1
 PKG_RELEASE:=1
 
-PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
+PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=@GNU/patch
-PKG_MD5SUM:=95dd8d7e41dcbcecdd5cd88ef915378d
+PKG_MD5SUM:=e9ae5393426d3ad783a300a338c09b72
 
 include $(INCLUDE_DIR)/package.mk