bootstub: only build for moorefield, merrifield [DO NOT MERGE]

Change-Id: I469f48f8b89e8b05587a6fdd944dee0327083bb7
(cherry picked from commit 2c7051d879b0a9c03d4178f642be7c3e5778b703)
diff --git a/Android.mk b/Android.mk
index 5dab544..590d1a8 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1,5 +1,7 @@
 LOCAL_PATH := $(call my-dir)
 
+ifneq ($(filter moorefield merrifield, $(TARGET_BOARD_PLATFORM)),)
+
 include $(CLEAR_VARS)
 # bootstub.bin
 BOOTSTUB_BINARY := bootstub
@@ -26,3 +28,5 @@
 BOOTSTUB_STACK_OFFSET := 0x78F00000
 BOOTSTUB_ENTRY := 0x78F00000
 include $(LOCAL_PATH)/bootstub.mk
+
+endif #($(filter moorefield merrifield, $(TARGET_BOARD_PLATFORM)),)