net: phy: broadcom: add support for BCM5221 phy

This patch adds the BCM5221 PHY support by reusing brcm_fet_*()
callbacks and adding quirks for BCM5221 when needed.

Cc: Jim Reinhart <jimr@tekvox.com>
Cc: James Autry <jautry@tekvox.com>
Cc: Matthew Maron <matthewm@tekvox.com>
Signed-off-by: Giulio Benetti <giulio.benetti+tekvox@benettiengineering.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20231005182915.153815-1-giulio.benetti@benettiengineering.com


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