ARM: sh-mobile: Use of_cpu_node_to_id() to read CPU node 'reg'

Replace open coded CPU nodes reading of "reg" and translation to logical
ID with of_cpu_node_to_id().

The original code called of_parse_phandle() CONFIG_NR_CPUS times
regardless of the length of 'cpus'. Optimize the loop to bail out once
of_parse_phandle() fails as the end of 'cpus' property has been reached.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230327205228.573456-1-robh@kernel.orgSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm/mach-shmobile/platsmp-apmu.c

@@ -10,6 +10,7 @@
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
+#include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/smp.h>
 #include <linux/suspend.h>
@@ -210,7 +211,6 @@ static void apmu_parse_dt(void (*fn)(struct resource *res, int cpu, int bit))
 	struct device_node *np_apmu, *np_cpu;
 	struct resource res;
 	int bit, index;
-	u32 id;
 
 	for_each_matching_node(np_apmu, apmu_ids) {
 		/* only enable the cluster that includes the boot CPU */
@@ -218,35 +218,31 @@ static void apmu_parse_dt(void (*fn)(struct resource *res, int cpu, int bit))
 
 		for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
 			np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
-			if (np_cpu) {
-				if (!of_property_read_u32(np_cpu, "reg", &id)) {
-					if (id == cpu_logical_map(0)) {
+			if (!np_cpu)
+				break;
+			if (of_cpu_node_to_id(np_cpu) == 0) {
 				is_allowed = true;
 				of_node_put(np_cpu);
 				break;
 			}
-
-				}
 			of_node_put(np_cpu);
 		}
-		}
 		if (!is_allowed)
 			continue;
 
 		for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
 			np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
-			if (np_cpu) {
-				if (!of_property_read_u32(np_cpu, "reg", &id)) {
-					index = get_logical_index(id);
+			if (!np_cpu)
+				break;
+
+			index = of_cpu_node_to_id(np_cpu);
 			if ((index >= 0) &&
-					    !of_address_to_resource(np_apmu,
-								    0, &res))
+			    !of_address_to_resource(np_apmu, 0, &res))
 				fn(&res, index, bit);
-				}
+
 			of_node_put(np_cpu);
 		}
 	}
-	}
 }
 
 static void __init shmobile_smp_apmu_setup_boot(void)