Fix broken unit test build.

Change-Id: I6b12b24379e5374644440111a4ffae71c4d8229e

Author: Juha Heiskanen

test/nanostack/unittest/thread/thread_bootstrap/Makefile

@@ -75,6 +75,7 @@ TEST_SRC_FILES = \
         ../../stub/thread_mle_message_handler_stub.c \
         ../../stub/thread_extension_bootstrap_stub.c \
         ../../stub/etx_stub.c \
+        ../../stub/adaptation_interface_stub.c \
 
 
 include ../../MakefileWorker.mk