LU-7903 mdt: dump exports information on console

LU-7903 mdt: dump exports information on console

To avoid being truncated in debug log, obd_exports_barrier() should
dump the exports information on console along with the "Is it stuck?"
warning message.

Test-Parameters: testlist=recovery-small,recovery-small,recovery-small
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Change-Id: I9dbaa7ed1d590db89ad6f42b66ec883dfb8b7ce1
Reviewed-on: http://review.whamcloud.com/21599
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>