ACPI: proc: Prefer to use octal permission

Octal permissions are preferred over the symbolics ones
for readbility. This ceases warning message pointed by checkpatch.

Signed-off-by: Andy Shevchenko <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/acpi/proc.c

···
 void __init acpi_sleep_proc_init(void)
 {
 	/* 'wakeup device' [R/W] */
-	proc_create("wakeup", S_IFREG | S_IRUGO | S_IWUSR,
-		    acpi_root_dir, &acpi_system_wakeup_device_proc_ops);
+	proc_create("wakeup", 0644, acpi_root_dir, &acpi_system_wakeup_device_proc_ops);
 }