dt-bindings: net: Convert fsl,gianfar-{mdio,tbi} to YAML

Move the information related to the Freescale Gianfar (TSEC) MDIO bus
and the Ten-Bit Interface (TBI) from fsl-tsec-phy.txt to a new binding
file in YAML format, fsl,gianfar-mdio.yaml.

Signed-off-by: J. Neuschäfer <j.ne@posteo.net>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20250228-gianfar-yaml-v2-1-6beeefbd4818@posteo.net


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