dt-bindings: net: fsl,fman: allow dma-coherent property

dt-bindings: net: fsl,fman: allow dma-coherent property

Add dma-coherent property to fix below warning.
arch/arm64/boot/dts/freescale/fsl-ls1046a-rdb.dtb: fman@1a00000: 'dma-coherent', 'ptimer-handle' do not match any of the regexes: '^ethernet@[a-f0-9]+$', '^mdio@[a-f0-9]+$', '^muram@[a-f0-9]+$', '^phc@[a-f0-9]+$', '^port@[a-f0-9]+$', 'pinctrl-[0-9]+'
	from schema $id: http://devicetree.org/schemas/net/fsl,fman.yaml#

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20240708180949.1898495-1-Frank.Li@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>