scsi: qedi: Move LL2 producer index processing in BH.

1. Removed logic to update HW producer index in interrupt context.

2. Update HW producer index after UIO ring and buffer gets initialized.

Signed-off-by: Manish Rangankar <manish.rangankar@cavium.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>