ubus: fix wrong PKG_SOURCE_DATE

Fix wrong PKG_SOURCE_DATE introduced in e14cac0

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

package/system/ubus/Makefile

@@ -5,7 +5,7 @@ PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/project/ubus.git
-PKG_SOURCE_DATE:=2018-11-13
+PKG_SOURCE_DATE:=2018-01-16
 PKG_SOURCE_VERSION:=5bae22eb5472c9c7cc30caa9a84004bba19940d3
 PKG_MIRROR_HASH:=21ceef22a34968d45c3eb2dd4106a7224fc53e13d6bc6937d4d4f5c070c9ff8a
 CMAKE_INSTALL:=1