ACPI: PAD: Use sysfs_emit() in idlecpus_show()

idlecpus_show() is a sysfs show callback. Use sysfs_emit() and
cpumask_pr_args() to emit the mask.

This prepares for removing cpumap_print_to_pagebuf().

Signed-off-by: Yury Norov <ynorov@nvidia.com>
[ rjw: Subject tweaks ]
Link: https://patch.msgid.link/20260528183625.870813-6-ynorov@nvidia.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: Yury Norov

drivers/acpi/acpi_pad.c

@@ -336,8 +336,8 @@ static ssize_t idlecpus_store(struct device *dev,
 static ssize_t idlecpus_show(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
-	return cpumap_print_to_pagebuf(false, buf,
-				       to_cpumask(pad_busy_cpus_bits));
+	return sysfs_emit(buf, "%*pb\n",
+			  cpumask_pr_args(to_cpumask(pad_busy_cpus_bits)));
 }
 
 static DEVICE_ATTR_RW(idlecpus);