brillo_update_payload should require simg2img. am: db537c18ef
am: 35caa57406

Change-Id: I2c145513ee6442bc0485fd87b103f3ab9c9d1f88
diff --git a/Android.mk b/Android.mk
index 528aa76..ff12e59 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1007,6 +1007,7 @@
 LOCAL_MODULE_TAGS := optional
 LOCAL_REQUIRED_MODULES := \
     delta_generator \
-    shflags
+    shflags \
+    simg2img
 include $(BUILD_PREBUILT)
 endif  # HOST_OS == linux