scsi: aic94xx: Fix a couple of misnamed function names

scsi: aic94xx: Fix a couple of misnamed function names

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

 drivers/scsi/aic94xx/aic94xx_hwi.c:910: warning: expecting prototype for ads_rbi_exsi_isr(). Prototype was for asd_rbi_exsi_isr() instead
 drivers/scsi/aic94xx/aic94xx_hwi.c:1156: warning: expecting prototype for asd_start_timers(). Prototype was for asd_start_scb_timers() instead

Link: https://lore.kernel.org/r/20210303144631.3175331-7-lee.jones@linaro.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Luben Tuikov <luben_tuikov@adaptec.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>