entd: fix problem problem with multi-second timeouts on ARM

BUG=chromium-os:160007
TEST=ran with pkcs11 failing on x86 and verified multiple-minute timeouts work correctly

Change-Id: If4a6cc8cdf8dc132d5520d183983d40144a93a56
Reviewed-on: http://gerrit.chromium.org/gerrit/2100
Tested-by: Ken Mixter <kmixter@chromium.org>
Reviewed-by: Sam Leffler <sleffler@chromium.org>