LU-1779 tests: fix run_one_logged() to log SKIP status

LU-1779 tests: fix run_one_logged() to log SKIP status

In the current test framework, only those tests which are in the
$ALWAYS_EXCEPT list are logged with SKIP status, other skipped
tests are all logged with PASS status.

This patch fixes the above issue by setting the SKIP status in
pass() and logging the status in run_one_logged().

Signed-off-by: Yu Jian <yujian@whamcloud.com>
Change-Id: Ia4e8f51040034abdec9c67aaf0a128b63baaa688
Reviewed-on: http://review.whamcloud.com/3810
Tested-by: Hudson
Reviewed-by: Minh Diep <mdiep@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>