unbound: plumb the libdir up

This is necessary for static builds where the linking is passed around
to dependent targets, but the library is lost.

external/CMakeLists.txt

@@ -84,7 +84,7 @@ if(NOT UNBOUND_INCLUDE_DIR OR STATIC)
   set(UNBOUND_STATIC true PARENT_SCOPE)
   set(UNBOUND_INCLUDE "${CMAKE_CURRENT_SOURCE_DIR}/unbound/libunbound" PARENT_SCOPE)
   set(UNBOUND_LIBRARY "unbound" PARENT_SCOPE)
-  set(UNBOUND_LIBRARY_DIRS "${LIBEVENT2_LIBRARY_DIRS}" PARENT_SCOPE)
+  set(UNBOUND_LIBRARY_DIRS "${LIBEVENT2_LIBDIR}" PARENT_SCOPE)
 else()
   message(STATUS "Found libunbound include (unbound.h) in ${UNBOUND_INCLUDE_DIR}")
   if(UNBOUND_LIBRARIES)

external/unbound/CMakeLists.txt

@@ -178,3 +178,8 @@ if (WIN32)
       iphlpapi
       ws2_32)
 endif ()
+
+# XXX: Hack for static builds.
+set(LIBEVENT2_LIBDIR
+  "${LIBEVENT2_LIBDIR}"
+  PARENT_SCOPE)