Use LKROOT as the path to LK am: ac0c10dc51

Original change: https://android-review.googlesource.com/c/trusty/app/avb/+/2870900

Change-Id: Ic0856cbfaa855ff1aaccf36e4a015064fac1c7ff
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/test/Makefile b/test/Makefile
index 40926b7..fab5e97 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -11,7 +11,7 @@
 	-I $(BASE)/lib/include \
 	-I $(AVBDIR) \
 	-I $(BASE)/lib/lib/libstdc++-trusty/include \
-	-I $(BASE)/external/lk/include/uapi \
+	-I $(BASE)/$(LKROOT)/include/uapi \
 	-I $(BASE)/lib/include/user \
 
 DEFINES := -DSTORAGE_FAKE