Use TARGET_BOARD_INFO_FILE to locate board-info.txt

So board-info.txt can be inherited from the parent device.

Change-Id: I5d99a2483b9a325e475f3c602d9e0f5d2b95e80c
diff --git a/CleanSpec.mk b/CleanSpec.mk
index 44cb05e..70a053f 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -94,6 +94,8 @@
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libstagefright_intermediates)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libstagefright_omx_intermediates)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/librtp_jni_intermediates)
+
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/android-info.txt)
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************
diff --git a/target/board/Android.mk b/target/board/Android.mk
index 54ee9e7..58164f6 100644
--- a/target/board/Android.mk
+++ b/target/board/Android.mk
@@ -27,10 +27,14 @@
 # with everything else.
 #
 # If the file "board-info.txt" appears in $(TARGET_DEVICE_DIR),
-# it will be appended to the output file.
+# it will be used; otherwise TARGET_BOARD_INFO_FILE is used, which
+# can be set in BoardConfig.mk.
 #
 INSTALLED_ANDROID_INFO_TXT_TARGET := $(PRODUCT_OUT)/android-info.txt
 board_info_txt := $(wildcard $(TARGET_DEVICE_DIR)/board-info.txt)
+ifndef board_info_txt
+board_info_txt := $(TARGET_BOARD_INFO_FILE)
+endif
 $(INSTALLED_ANDROID_INFO_TXT_TARGET): $(board_info_txt)
 	$(call pretty,"Generated: ($@)")
 ifdef board_info_txt