fix tiny android build

Change-Id: Ifa6cda67f54969588b5c4e9f900ac2d4ba607e71
Signed-off-by: Brian Swetland <swetland@google.com>
diff --git a/core/main.mk b/core/main.mk
index 9d8e692..4a530d0 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -455,6 +455,7 @@
 subdirs := \
 	bionic \
 	system/core \
+	system/extras/ext4_utils \
 	build/libs \
 	build/target \
 	build/tools/acp \