dt-bindings: lcdif: Document the dmas/dma-names properties

dt-bindings: lcdif: Document the dmas/dma-names properties

i.MX28 has an RX DMA channel associated with the LCDIF controller.

Document the 'dmas' and 'dma-names' properties to fix the following
dt-schema warnings:

lcdif@80030000: 'dma-names', 'dmas' do not match any of the regexes: 'pinctrl-[0-9]+'

Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240904104027.2065621-1-festevam@gmail.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>