Applications determine loop support in part by querying the 'pls' sysfs
node. Reporting of 'pls' (Private Loop Support) is derived from the
descriptor returned by the COMMON_GET_SLI4_PARAMETERS mailbox command,
which is issued during initialization or after a reset.

The value of this field may change if there is a dynamic SFP change.  The
driver currently will not pick up the change as there was no reset
scenario.

Rework to commonize the sending of the COMMON_GET_SLI4_PARAMETERS
command. Add the calling of the routine after receipt of an async event
indicating an SFP change.

Link: https://lore.kernel.org/r/20211020211417.88754-4-jsmart2021@gmail.comCo-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>