Respect VABC Xor prop in ota_from_target_files

Test: generate ota on a non-vabc xor target, make sure it's not used
Change-Id: Ibdbcfe3775c96848c37c7f580121583d4bd57fce
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index 1f3022b..366b51a 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -1091,6 +1091,9 @@
   if target_info.vendor_suppressed_vabc:
     logger.info("Vendor suppressed VABC. Disabling")
     OPTIONS.disable_vabc = True
+  if not target_info.is_vabc_xor or OPTIONS.disable_vabc:
+    logger.info("VABC XOR Not supported, disabling")
+    OPTIONS.enable_vabc_xor = False
   additional_args = []
 
   # Prepare custom images.