[SCSI] ses: fix VPD inquiry overrun

There are a few kerneloops.org reports like this one:

http://www.kerneloops.org/search.php?search=ses_match_to_enclosure

That seem to imply we're running off the end of the VPD inquiry data
(although at 512 bytes, it should be long enough for just about
anything).  we should be using correctly sized buffers anyway, so put
those in and hope this oops goes away.

Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>