tools / cpupower: Fix no idle state information return value

sysfs_get_idlestate_count() returns an unsigned int. Returning -ENODEV
is not the right thing to do here, and in any case is handled the same
way as if there are no states found.

Signed-off-by: Prarit Bhargava <[e-mail]>
Acked-by: Thomas Renninger <[e-mail]>
Signed-off-by: Rafael J. Wysocki <[e-mail]>

tools/power/cpupower/utils/helpers/sysfs.c

···
 
 	snprintf(file, SYSFS_PATH_MAX, PATH_TO_CPU "cpuidle");
 	if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))
-		return -ENODEV;
+		return 0;
 
 	snprintf(file, SYSFS_PATH_MAX, PATH_TO_CPU "cpu%u/cpuidle/state0", cpu);
 	if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))