net: phy: fixed_phy: replace list of fixed PHYs with static array

net: phy: fixed_phy: replace list of fixed PHYs with static array

Due to max 32 PHY addresses being available per mii bus, using a list
can't support more fixed PHY's. And there's no known use case for as
much as 32 fixed PHY's on a system. 8 should be plenty of fixed PHY's,
so use an array of that size instead of a list. This allows to
significantly reduce the code size and complexity.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/8610d30c-eac7-4100-9008-d3b6cee6a5cd@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>