ARM: dts: bcm28155-ap: use node labels

Use node labels instead of nodename@address for BCM28155 AP board
to simplify its DTS file.

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Link: https://lore.kernel.org/r/20230718165319.GA5179@standask-GA-A55M-S2HP


Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>