dt-bindings: clock: mpfs-ccc: Add pic64gx compatibility

pic64gx SoC Clock Conditioning Circuitry is compatibles
with the Polarfire SoC

Signed-off-by: Pierre-Henry Moussay <pierre-henry.moussay@microchip.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20260113-guise-conceded-88030697b831@spud
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>