scsi: hpsa: use %phN for short hex dumps

Passing one instead of 8 or 16 arguments reduces the size of the
generated code somewhat:

add/remove: 2/3 grow/shrink: 1/4 up/down: 1772/-2137 (-365)

There's one more candidate, unique_id_show, but that uses %02X, and I'm
not sure it would be ok to start using lowercase there, so I've left it
alone for now.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>