configurable defaults: deps and cc_deps - where needed?

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Some rules have global configurable default settings for deps and cc_deps. These can be used to do things like adding jemalloc or bisect_ppx everywhere.

For example, to add jemalloc to all executables: --@ocaml//executable:cc_deps=@ocaml_jemalloc//src:libjemalloc

Design issue: which rules need this capability? Specifically, are they needed for ocaml_interface?