ACPI: sysfs: Refactor param_get_trace_state() to drop dead code

The param_get_trace_state() has a few dead code issues:
 - 'return 0;' is never reachable
 - a few 'else' keywords are redundant

Refactor param_get_trace_state() to drop dead code.

Note, leave one 'else' in order to have the best readability.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/sysfs.c

@@ -255,16 +255,12 @@ static int param_get_trace_state(char *buffer, const struct kernel_param *kp)
 {
 	if (!(acpi_gbl_trace_flags & ACPI_TRACE_ENABLED))
 		return sprintf(buffer, "disable\n");
-	else {
-		if (acpi_gbl_trace_method_name) {
-			if (acpi_gbl_trace_flags & ACPI_TRACE_ONESHOT)
-				return sprintf(buffer, "method-once\n");
-			else
-				return sprintf(buffer, "method\n");
-		} else
-			return sprintf(buffer, "enable\n");
-	}
-	return 0;
+	if (!acpi_gbl_trace_method_name)
+		return sprintf(buffer, "enable\n");
+	if (acpi_gbl_trace_flags & ACPI_TRACE_ONESHOT)
+		return sprintf(buffer, "method-once\n");
+	else
+		return sprintf(buffer, "method\n");
 }
 
 module_param_call(trace_state, param_set_trace_state, param_get_trace_state,