scsi: call device handler for failed TUR command

Multipath devices using the TUR path checker need to see the sense
code for a failed TUR command in their device handler.  Since commit
14216561

 we always return success for mid
layer issued TUR commands before calling the device handler, which
stopped the TUR path checker from working.

Move the call to the device handler check sense method before the early
return for TUR commands to give the device handler a chance to intercept
them.

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Tested-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>