optional cross-check between OTA radio images and board-info.txt

Adds a python script which checks the version of each radio image
added with the new add-radio-file-checked macro against a file
containing sha-1 -> version string mappings and the contents of
board-info.txt, so that the build can fail if board-info.txt and the
OTA images are out of sync.

Change-Id: Icb61dc2adefc240ced9059941582c23b629089c0
diff --git a/target/board/Android.mk b/target/board/Android.mk
index 6f3bf91..7d94ee0 100644
--- a/target/board/Android.mk
+++ b/target/board/Android.mk
@@ -36,6 +36,7 @@
 board_info_txt := $(wildcard $(TARGET_DEVICE_DIR)/board-info.txt)
 endif
 $(INSTALLED_ANDROID_INFO_TXT_TARGET): $(board_info_txt)
+	$(hide) build/tools/check_radio_versions.py $< $(BOARD_INFO_CHECK)
 	$(call pretty,"Generated: ($@)")
 ifdef board_info_txt
 	$(hide) grep -v '#' $< > $@