scsi: qla1280: make qla1280_firmware_mutex and qla1280_fw_tbl static

scsi: qla1280: make qla1280_firmware_mutex and qla1280_fw_tbl static

Fix the following sparse warning:

drivers/scsi/qla1280.c:529:1: warning: symbol 'qla1280_firmware_mutex'
was not declared. Should it be static?
drivers/scsi/qla1280.c:538:15: warning: symbol 'qla1280_fw_tbl' was not
declared. Should it be static?

Link: https://lore.kernel.org/r/20200409084910.44336-1-yanaijie@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>