realtek: rtl93xx: remove pseudo-PHYs and phy-handle from SFP ports

realtek: rtl93xx: remove pseudo-PHYs and phy-handle from SFP ports

RTL93XX reached the point where the SerDes' are no longer treated as
regular PHYs. Instead, they are managed by the dedicated PCS driver.
Thus, all device tree definitions should follow this change.

Remove the pseudo-PHYs for the SerDes (so far usually defined with macro
INTERNAL_PHY) and corresponding 'phy-handle's from all SFP ports. This
removes a long-lasting confusion from our Realtek driver(s).

Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/20577
Signed-off-by: Robert Marko <robimarko@gmail.com>