Merge branch 'doc-sfp-phylink-update-the-porting-guide'

Maxime Chevallier says:

====================
doc: sfp-phylink: update the porting guide

Here's a V3 for an update on the phylink porting guide. The only
difference with V2 is a whitespace fix along with a line-wrap.

The main point of the update is the description of a basic process to
follow to expose one or more PCS to phylink. Let me know if you spot any
inaccuracies in the guide.

The second patch is a simple fixup on some in-code doc that was spotted
while updating the guide.

Link to V2: https://lore.kernel.org/netdev/20240228095755.1499577-1-maxime.chevallier@bootlin.com/
Link to V1: https://lore.kernel.org/netdev/20240220160406.3363002-1-maxime.chevallier@bootlin.com/
====================

Link: https://lore.kernel.org/r/20240301164309.3643849-1-maxime.chevallier@bootlin.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>