Extend the devlink health reporter registered by mlxsw to report new
health events and their related parameters. These are meant to aid in
debugging of hardware / firmware issues.

Beside the test event ('MLXSW_REG_MFDE_EVENT_ID_TEST') that is triggered
following the devlink health 'test' sub-command, the new events are used
to report the triggering of asserts in firmware code
('MLXSW_REG_MFDE_EVENT_ID_FW_ASSERT') and hardware issues
('MLXSW_REG_MFDE_EVENT_ID_FATAL_CAUSE').

Each event is accompanied with a severity parameter and per-event
parameters that are meant to help root cause the detected issue.
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>