daemon: Remove -DGerritServer from documentation

Since fb5548efcb05 ("Configure database from gerrit.config") we have
stopped reading GerritServer.properties during startup and instead
use the $site_path/gerrit.config.

Change-Id: Iffb06d22757c068a1436774fd66a178e8b1b801b
Signed-off-by: Shawn O. Pearce <sop@google.com>
1 file changed