AT_CHECK_MACRO: Preserve config.log and config.status from run 1.

AT_CHECK_MACRO: Preserve config.log and config.status from run 1.

AT_CHECK_MACRO runs a test configure script twice and looks for
differences in the results.  If something goes wrong, it’ll be helpful
for debugging to preserve the config.log and config.status files from
both runs.

* tests/local.at (AT_CHECK_MACRO): Also copy config.log and
  config.status to config-log.$at_run and config-status.$at_run
  respectively.