[SCSI] mpt2sas: Prevent sending command to FW while Host Reset

This patch renames the flag for indicating host reset from
ioc_reset_in_progress to shost_recovery. It also removes the spin locks
surrounding the setting of this flag, which are unnecessary.   Sanity checks on
the shost_recovery flag were added thru out the code so as to prevent sending
firmware commands during host reset.  Also, the setting of the shost state to
SHOST_RECOVERY was removed to prevent deadlocks, this is actually better
handled by the shost_recovery flag.

Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Reviewed-by: Eric Moore <Eric.moore@lsi.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>