arm64: dts: ls1028a: Add optional property node for Mali DP500

This patch use the optional property node "arm,malidp-arqos-value" to
can be dynamic configure QoS signaling.

Signed-off-by: Wen He <wen.he_1@nxp.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>