Added support for flash image in both slots

Change-Id: Iafda62a5f77f7c1f564f1a2ec0a59aefaf5e1266
diff --git a/gui/Android.mk b/gui/Android.mk
index 59a2624..33e870f 100755
--- a/gui/Android.mk
+++ b/gui/Android.mk
@@ -116,6 +116,9 @@
 ifeq ($(TW_EXCLUDE_NANO), true)
     LOCAL_CFLAGS += -DTW_EXCLUDE_NANO
 endif
+ifeq ($(AB_OTA_UPDATER),true)
+    LOCAL_CFLAGS += -DAB_OTA_UPDATER=1
+endif
 
 LOCAL_C_INCLUDES += \
     bionic \