Add a check for missing entries in AVB_FOOTER_ARGS_BY_PARTITION

Fail the signing if the AVB_FOOTER_ARGS_BY_PARTITION isn't in sync
with common.AVB_PARTITIONS.

Bug: 181787095
Test: run sign_target_files_apks on a S image

Change-Id: I6ccf5fb9f39b92c1da2554f5b3826d2cd87d84d7
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index fc1a692..0061819 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -109,7 +109,9 @@
 
 # The partitions allowed to be signed by AVB (Android Verified Boot 2.0). Note
 # that system_other is not in the list because we don't want to include its
-# descriptor into vbmeta.img.
+# descriptor into vbmeta.img. When adding a new entry here, the
+# AVB_FOOTER_ARGS_BY_PARTITION in sign_target_files_apks need to be updated
+# accordingly.
 AVB_PARTITIONS = ('boot', 'dtbo', 'odm', 'product', 'pvmfw', 'recovery',
                   'system', 'system_ext', 'vendor', 'vendor_boot',
                   'vendor_dlkm', 'odm_dlkm')