scsi: lpfc: Fix I/O block after enabling managed congestion mode

If the congestion management framework dynamically enables, it may do so
while I/O is in flight. The updates of cmf info due to inflight I/O
completing may happen before values have been initialized.

Fix by ensure cmf_max_bytes_per_interval is initialized when checking
bandwidth utilization for SCSI layer blocking.

Link: https://lore.kernel.org/r/20210910233159.115896-12-jsmart2021@gmail.com


Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>