scsi: qedi: make qedi_ll2_buf_size static

Fix the following sparse warning:

drivers/scsi/qedi/qedi_main.c:44:6: warning: symbol 'qedi_ll2_buf_size' was
not declared. Should it be static?

Link: https://lore.kernel.org/r/20200415085029.7170-1-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>