Rename variable to match option parsing variable name (again)

The object_timeout variable was renamed object_sync_timeout
in the option parser, but not elsewhere.

This patch fixes it.

Signed-off-by: Christophe Courtaut <christophe.courtaut@gmail.com>
Merge pull request #5 from kri5/wip-datasync

Rename variable to match option parsing variable name (again)

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>