AVB: If building recovery.img, add AVB hash footer.

In some non-A/B setups, recovery.img is still being used. If AVB is
enabled, we currently don't add a hash footer to recovery.img nor do
we include the hash digest in vbmeta.img. This CL fixes that.

This was tested on a build with the following settings

 TARGET_NO_RECOVERY := false
 BOARD_USES_RECOVERY_AS_BOOT := false
 BOARD_BUILD_SYSTEM_ROOT_IMAGE := false
 BOARD_RECOVERYIMAGE_PARTITION_SIZE := 33554432
 BOARD_AVB_RECOVERY_ADD_HASH_FOOTER_ARGS := --prop foo:bar

and then it was verified using 'avbtool info_image' that recovery.img
has a hash footer and a 'foo' property with the value 'bar'. This was
also checked successfully for vbmeta.img.

Test: See above.
Bug: None
Change-Id: I98124d5661ea768411416fa8d2a2ae6cc664fdc8

tools/releasetools/common.py

@@ -500,15 +500,15 @@ def _BuildBootableImage(sourcedir, fs_config_file, info_dict=None,
     img_unsigned.close()
     img_keyblock.close()
 
-  # AVB: if enabled, calculate and add hash to boot.img.
+  # AVB: if enabled, calculate and add hash to boot.img or recovery.img.
   if info_dict.get("avb_enable") == "true":
     avbtool = os.getenv('AVBTOOL') or info_dict["avb_avbtool"]
-    part_size = info_dict["boot_size"]
+    part_size = info_dict[partition_name + "_size"]
     cmd = [avbtool, "add_hash_footer", "--image", img.name,
            "--partition_size", str(part_size), "--partition_name",
            partition_name]
     AppendAVBSigningArgs(cmd, partition_name)
-    args = info_dict.get("avb_boot_add_hash_footer_args")
+    args = info_dict.get("avb_" + partition_name + "_add_hash_footer_args")
     if args and args.strip():
       cmd.extend(shlex.split(args))
     p = Run(cmd, stdout=subprocess.PIPE)