am c170360d: am b2c79174: am ca983c08: am 97c280ec: Merge "We have to use := instead of +="

* commit 'c170360d964fe83e0f1b58c6f7369daaf9aebdd8':
  We have to use := instead of +=
diff --git a/core/base_rules.mk b/core/base_rules.mk
index cffaa94..d03050b 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -448,7 +448,7 @@
 ###########################################################
 cleantarget := clean-$(LOCAL_MODULE)
 $(cleantarget) : PRIVATE_MODULE := $(LOCAL_MODULE)
-$(cleantarget) : PRIVATE_CLEAN_FILES += \
+$(cleantarget) : PRIVATE_CLEAN_FILES := \
     $(LOCAL_BUILT_MODULE) \
     $(LOCAL_INSTALLED_MODULE) \
     $(intermediates)