[submodule]: update sonic-sairedis

* afe2a0d 2019-10-30 | [vs]: Fix learn fdb events after fdb flush event (#524) (HEAD, origin/master, origin/HEAD) [Kamil Cudnik]
* d29760f 2019-10-28 | [sai_redis_interface_query] Add sairedis support for sai_object_type_get_availability (#528) [Danny Allen]
* ff5306e 2019-10-28 | [sai_redis_interface_query] Add sairedis support for sai_query_attribute_enum_values_capability (#525) [Danny Allen]

Signed-off-by: Guohan Lu <gulv@microsoft.com>