MRP-1396 obdstack: not able to unlink selfexport

if we have access to the obddevice via num2obd or name2obd functions
during cleanup we may hit a situation when we re-enter into ioctl
when we have destroy in flight and current code tried to unlink
selfexport twice.
Patch avoid unlinking selfexport twice and reorder the obdcleanup.

Change-Id: Ie96cc6ba259cd8bba74447b1d102275a9a69edb4
Signed-off-by: Alexey Lyashkov <alexey_lyashkov@xyratex.com>
MRP-1848 ptlrpc: wait to unregister send buffer also.

add waiting an request buffer to unregister phase, to avoid
unlinking request when LNet hold an reference to the sending
buffer.

Signed-off-by: Alexey Lyashkov <alexey_lyashkov@xyratex.com>
Change-Id: I77a65d062e293770f23208a930fcb154848ee67c
Reviewed-on: http://es-gerrit.xyus.xyratex.com:8080/2186
Tested-by: Jenkins
Reviewed-by: Andrew Perepechko <andrew_perepechko@xyratex.com>
Tested-by: Elena Gryaznova <elena_gryaznova@xyratex.com>
Reviewed-by: Vitaly Fertman <vitaly_fertman@xyratex.com>