ISP2200 adapters only have 24 mailbox registers so read only that many.
Reported-by: Olatunji Ruwase <oor@cs.cmu.edu>
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>