Merge branch 'mlxsw-Expose-transceiver-overheat-counter'

Ido Schimmel says:

====================
mlxsw: Expose transceiver overheat counter

Amit says:

An overheated transceiver can be the root cause of various network
problems such as link flapping. Counting the number of times a
transceiver's temperature was higher than its configured threshold can
therefore help in debugging such issues.

This patch set exposes a transceiver overheat counter via ethtool. This
is achieved by configuring the Spectrum ASIC to generate events whenever
a transceiver is overheated. The temperature thresholds are queried from
the transceiver (if available) and set to the default otherwise.

Example:

...
transceiver_overheat: 2

Patch set overview:

Patches #1-#3 add required device registers
Patches #4-#5 add required infrastructure in mlxsw to configure and
count overheat events
Patches #6-#9 gradually add support for the transceiver overheat counter
Patch #10 exposes the transceiver overheat counter via ethtool
====================

Signed-off-by: David S. Miller <davem@davemloft.net>