scsi: message: fusion: Remove redundant variable iocnum

Variable iocnum is assigned a value that is never read, the assignment and
hence the variable are redundant can be removed. Also update the comment to
reflect the correct name of the variable being updated.

Cleans up clang-scan warning:

drivers/message/fusion/mptctl.c:641:8: warning: Although the value stored
to 'iocnum' is used in the enclosing expression, the value is never
actually read from 'iocnum' [deadcode.DeadStores]

Link: https://lore.kernel.org/r/20220805113214.2339022-1-colin.i.king@gmail.com


Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>