arm64: dts: ipq6018: drop standalone 'smem' node

Since commit b5af64fc ("soc: qcom: smem: Support reserved-memory
description") the SMEM device can be instantiated directly from a
reserved-memory node.

The 'smem' node is defined in this way for each modern IPQ SoCs except for
IPQ6018. In order to make it inline with the others, move the 'compatible'
and the 'hwlock' properties into the respective reserved-memory node, and
drop the standalone 'smem' node.

Signed-off-by: Gabor Juhos <j4g8y7@gmail.com>
Reviewed-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250506-ipq6018-drop-smem-v1-1-af99d177be2f@gmail.com


Signed-off-by: Bjorn Andersson <andersson@kernel.org>