Drop --enable-cc-silence parameter from jemalloc
Drop --enable-cc-silence parameter from jemalloc

In jemalloc v4.0.0, --enable-cc-silence was flipped in favor of
--disable-cc-silence in
https://github.com/jemalloc/jemalloc/commit/644d414bc, so we don't need
this parameter anymore.

gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab