Revert "core/advertising: Fix ManufaturerData dict type"

This reverts commit d4a4c05a66e4c4ec8febdb0cab29c653938ad915, the type
was correct since it is the byte array after the key that is being
parsed.
diff --git a/src/advertising.c b/src/advertising.c
index 79b6042..d2019de 100644
--- a/src/advertising.c
+++ b/src/advertising.c
@@ -302,7 +302,7 @@
 
 		dbus_message_iter_recurse(&entry, &value);
 
-		if (dbus_message_iter_get_arg_type(&value) != DBUS_TYPE_UINT16)
+		if (dbus_message_iter_get_arg_type(&value) != DBUS_TYPE_BYTE)
 			goto fail;
 
 		dbus_message_iter_get_fixed_array(&value, &manuf_data, &len);