ARM: dts: s5pv210: align DMA channels with dtschema

dtschema expects DMA channels in specific order (tx, rx and tx-sec).
The order actually should not matter because dma-names is used however
let's make it aligned with dtschema to suppress warnings like:

  i2s@eee30000: dma-names: ['rx', 'tx', 'tx-sec'] is not valid under any of the given schemas

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Co-developed-by: Jonathan Bakker <xc-racer2@live.ca>
Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Link: https://lore.kernel.org/r/CY4PR04MB056779A9C50DC95987C5272ACB1C9@CY4PR04MB0567.namprd04.prod.outlook.com


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>