scsi: csiostor: Fix misnamed function parameter

scsi: csiostor: Fix misnamed function parameter

Fixes the following W=1 kernel build warning(s):

 drivers/scsi/csiostor/csio_init.c:595: warning: Function parameter or member 'pln' not described in 'csio_shost_init'
 drivers/scsi/csiostor/csio_init.c:595: warning: Excess function parameter 'os_pln' description in 'csio_shost_init'

Link: https://lore.kernel.org/r/20200721164148.2617584-32-lee.jones@linaro.org
Cc: Saurav Girepunje <saurav.girepunje@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>