prefer an explicitly-set TARGET_BOARD_INFO_FILE

Change-Id: Ie667a4d0070d1f0bbdfe9fa6d96871bcceb959b8
diff --git a/target/board/Android.mk b/target/board/Android.mk
index 58164f6..6f3bf91 100644
--- a/target/board/Android.mk
+++ b/target/board/Android.mk
@@ -26,19 +26,19 @@
 # device we're building for.  This file is typically packaged up
 # with everything else.
 #
-# If the file "board-info.txt" appears in $(TARGET_DEVICE_DIR),
-# it will be used; otherwise TARGET_BOARD_INFO_FILE is used, which
-# can be set in BoardConfig.mk.
+# If TARGET_BOARD_INFO_FILE (which can be set in BoardConfig.mk) is
+# defined, it is used, otherwise board-info.txt is looked for in
+# $(TARGET_DEVICE_DIR).
 #
 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)
+ifndef board_info_txt
+board_info_txt := $(wildcard $(TARGET_DEVICE_DIR)/board-info.txt)
 endif
 $(INSTALLED_ANDROID_INFO_TXT_TARGET): $(board_info_txt)
 	$(call pretty,"Generated: ($@)")
 ifdef board_info_txt
-	$(hide) cat $< > $@
+	$(hide) grep -v '#' $< > $@
 else
 	$(hide) echo "board=$(TARGET_BOOTLOADER_BOARD_NAME)" > $@
 endif