arm64: dts: imx8qm-ss-img: Fix jpegenc compatible entry

The first compatible entry for the jpegenc should be 'nxp,imx8qm-jpgenc'.

Change it accordingly to fix the following schema warning:

imx8qm-apalis-eval.dtb: jpegenc@58450000: compatible: 'oneOf' conditional failed, one must be fixed:
	'nxp,imx8qm-jpgdec' is not one of ['nxp,imx8qxp-jpgdec', 'nxp,imx8qxp-jpgenc']
	'nxp,imx8qm-jpgenc' was expected
	'nxp,imx8qxp-jpgdec' was expected

Fixes: 5bb27917 ("arm64: dts: imx8: Add jpeg encoder/decoder nodes")
Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Mirela Rabulea <mirela.rabulea@nxp.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>