net: phylink: restrict SFP interfaces to those that are supported

When configuring an optical SFP interface, restrict the bitmap of SFP
interfaces (pl->sfp_interfaces) to those that are supported by the
host, rather than calculating this in a local variable.

This will allow us to avoid recomputing this in the
phylink_ethtool_ksettings_set() path.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/E1uWu0u-005KXc-A4@rmk-PC.armlinux.org.uk


Signed-off-by: Jakub Kicinski <kuba@kernel.org>