scsi: lpfc: Enhance congestion statistics collection
Various improvements are made for collecting congestion statistics:
- Pre-existing logic is replaced with use of an hrtimer for increased
reporting accuracy.
- Congestion timestamp information is reorganized into a single struct.
- Common statistic collection logic is refactored into a helper routine.
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20230523183206.7728-8-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>