bnxt_en: implement dump callback for fw health reporter

Populate the dump with firmware 'live' coredump data. This includes
the information stored in NVRAM by the firmware exception handler
prior to recovery. Thus, the live dump includes the desired crash
context.

Firmware does not support HWRM calls after RESET_NOTIFY, so there is
no supported way to capture a coredump during the auto dump phase.
Detect this and abort when called from devlink_health_report().

Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>