dt-bindings: mpam: refactor device tree node structure

arm64/mpam: refactor device tree structure to support multiple
devices

ascend inclusion
category: feature
bugzilla:
https://gitee.com/openeuler/kernel/issues/I49RB2
CVE: NA

---------------------------------------------------

To support multiple mpam device nodes, all nodes should be organized
as child of the same parent nodes. This makes sure that the mpam
discovery start and complete procedure in the right execution order.
Add modification in the devicetree documentation to record this.
Signed-off-by: NXingang Wang <wangxingang5@huawei.com>
Signed-off-by: NWang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: NCheng Jian <cj.chengjian@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

Documentation/devicetree/bindings/arm/arm,mpam.txt

@@ -28,8 +28,10 @@ and Monitoring (MPAM), for Armv8-A", MPAM interrupts(section 8.8).
 
 Example:
 
-mpam_memory0 {
+mpam {
 	compatible = "arm,mpam";
+
+	mpam_memory0 {
 		reg = <0x0 0x10000000 0x0 0x10000>;
 		type = <2>; /* memory type */
 		numa-node-id = <0>;
@@ -38,10 +40,9 @@ mpam_memory0 {
 		error-interrupt = <0>;
 		error-interrupt-flags = <0>;
 		not-ready-max = <0>;
-};
+	};
 
-mpam_cache0 {
-	compatible = "arm,mpam";
+	mpam_cache0 {
 		reg = <0x0 0x20000000 0x0 0x10000>;
 		type = <1>; /* cache type */
 		cache-id = <0>;
@@ -51,4 +52,6 @@ mpam_cache0 {
 		error-interrupt = <0>;
 		error-interrupt-flags = <0>;
 		not-ready-max = <0>;
+	};
+
 };