arm64: dts: imx8-ss-img: Assign slot for imx jpeg encoder/decoder

assign a single slot,
configure interrupt and power domain only for 1 slot,
not for the all 4 slots.

Signed-off-by: Ming Qian <ming.qian@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>