LU-7535 mdt: clear the lock handle in mdt_intent_layout()

LU-7535 mdt: clear the lock handle in mdt_intent_layout()

In mdt_intent_layout() if the object cannot be found then clear the
lock handle. In recover-small add test_130c() to check that this is
handled condition is handled safely.

In recovery-small test_130[ab]() add a synt to avoid having an
unintended layout intent RPC (from writeback) hit the fault injection
point.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: Ic2f401ff2dc8a83467b12d146f4d7ffdf70ef5da
Reviewed-on: http://review.whamcloud.com/17735
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>