MB-100: disable erlc warnings on deprecated functions

It should partially unbreak compilation under R16B01.

And in general this is second time they introduce new api and
_immediately_ deprecate old one. So -Werror is not reall usable
without disabling that deprecation warning.

Change-Id: I0bcb043dece800ce32e3acaa9626db14dec6cd12
Reviewed-on: http://review.couchbase.org/27556
Reviewed-by: Filipe David Borba Manana <fdmanana@gmail.com>
Tested-by: Filipe David Borba Manana <fdmanana@gmail.com>