pcc_freq: convert acpi_get_handle() to acpi_has_method()

acpi_has_method() is a new ACPI API introduced to check
the existence of an ACPI control method.

It can be used to replace acpi_get_handle() in the case that
1. the calling function doesn't need the ACPI handle of the control method.
and
2. the calling function doesn't care the reason why the method is unavailable.

Convert acpi_get_handle() to acpi_has_method()
in drivers/cpufreq/pcc_freq.c in this patch.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/pcc-cpufreq.c

@@ -396,15 +396,14 @@ static int __init pcc_cpufreq_probe(void)
 	struct pcc_memory_resource *mem_resource;
 	struct pcc_register_resource *reg_resource;
 	union acpi_object *out_obj, *member;
-	acpi_handle handle, osc_handle, pcch_handle;
+	acpi_handle handle, osc_handle;
 	int ret = 0;
 
 	status = acpi_get_handle(NULL, "\\_SB", &handle);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
 
-	status = acpi_get_handle(handle, "PCCH", &pcch_handle);
-	if (ACPI_FAILURE(status))
+	if (!acpi_has_method(handle, "PCCH"))
 		return -ENODEV;
 
 	status = acpi_get_handle(handle, "_OSC", &osc_handle);