dt-bindings: thermal: fsl,scu-thermal: Document imx8dl

dt-bindings: thermal: fsl,scu-thermal: Document imx8dl

imx8dxl also contains the SCU thermal block.

Add an entry for 'fsl,imx8dxl-sc-thermal'.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Amit Kucheria <amitk@kernel.org>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230926122957.341094-5-festevam@gmail.com