libubox: fix package bump

The previous commit was incorrectly rebased and referred to a not
yet existing PROJECT_GIT variable.

Fixes: d86a269c1f libubox: update to latest git HEAD
Signed-off-by: Jo-Philipp Wich <[email protected]>

package/libs/libubox/Makefile

@@ -4,10 +4,10 @@ PKG_NAME:=libubox
 PKG_RELEASE=1
 
 PKG_SOURCE_PROTO:=git
-PKG_SOURCE_URL=$(PROJECT_GIT)/project/libubox.git
-PKG_SOURCE_DATE:=2017-10-06
-PKG_SOURCE_VERSION:=729f47fd5279f902986457682f8f166c324eafb5
-PKG_MIRROR_HASH:=5ca03294498f347f437236aeb1d55747264229a46a5ddba93caeb6b3fb735e10
+PKG_SOURCE_URL=$(LEDE_GIT)/project/libubox.git
+PKG_SOURCE_DATE:=2018-01-07
+PKG_SOURCE_VERSION:=1c08e80313fd487112c48346889cc57badeef751
+PKG_MIRROR_HASH:=58cad98de55d44d7791e5d49b809ac5c32d3e6c481dc385b10e02386853f2263
 CMAKE_INSTALL:=1
 
 PKG_LICENSE:=ISC