LU-5079 ptlrpc: fix early reply timeout for recovery

LU-5079 ptlrpc: fix early reply timeout for recovery

Commit 8b2f9c0e408 http://review.whamcloud.com/9100 changed
the deadline calculation from current time to request arrival.
During recovery, the new deadline could be less than calculated
at request arrival time. And even worse, the deadline may be
in past. For the first case unneeded early reply would be sent
to client. For the second, client requests would be dropped by
timeout and client reconnect happend.

Do at_measured() for recovery in the same way like general early
reply base on the current time. And set new timeout to the end
of recovery.

Test to check recovery deadline bug.

The patch also speeds up replay-vbr test 7* by decreasing the
at_max value in test_7_cycle().

This patch is back-ported from the following one:
Lustre-commit: 1d889090f2e2902d861d1fab0227c4343127cc42
Lustre-change: http://review.whamcloud.com/11213

Test-Parameters: alwaysuploadlogs \
envdefinitions=SLOW=yes,ENABLE_QUOTA=yes \
mdtfilesystemtype=ldiskfs mdsfilesystemtype=ldiskfs ostfilesystemtype=ldiskfs \
clientdistro=el6 ossdistro=el6 mdsdistro=el6 \
mdtcount=1 mdssizegb=2 ostcount=7 ostsizegb=2 \
testlist=replay-vbr,replay-vbr

Xyratex-bug-id: MRP-1988

Change-Id: I7a5d60ca8e52a805546cc9934eb42bddeaf8ff4e
Signed-off-by: Alexander Boyko <alexander_boyko@xyratex.com>
Signed-off-by: Jian Yu <jian.yu@intel.com>
Reviewed-on: http://review.whamcloud.com/12365
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>