arm64: dts: qcom: sm8550: Enable download mode register write

Enable download mode setting for sm8550 which can help collect
ramdump for this SoC.
Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
Link: https://lore.kernel.org/r/1698253601-11957-4-git-send-email-quic_mojha@quicinc.com
[bjorn: Updated tcsr offset, per Mukesh correction]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

arch/arm64/boot/dts/qcom/sm8550.dtsi

@@ -324,6 +324,7 @@ CLUSTER_SLEEP_1: cluster-sleep-1 {
 	firmware {
 		scm: scm {
 			compatible = "qcom,scm-sm8550", "qcom,scm";
+			qcom,dload-mode = <&tcsr 0x19000>;
 			interconnects = <&aggre2_noc MASTER_CRYPTO 0 &mc_virt SLAVE_EBI1 0>;
 		};
 	};