Remove a number of check/do_work wrapper calls from coarse_timers

Remove a number of check/do_work wrapper calls from coarse_timers

This indirection is not very helpful in understanding the code
flow.  Move the check to process_coarse_timers, remove the
check function, rename the do_work function to the "real" thing
and then drop the do_work wrapper as it does no longer serve a
purpose.

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20200810143707.5834-7-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg20668.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>