This reverts commit 35d13c7a05.
This broke procfs interface due to neglecting the fact that
the strings are not coming NULL terminated.
Revert the change till we will have a better clean up.
Fixes: 35d13c7a05 ("platform/x86: thinkpad_acpi: Use strndup_user() in dispatch_proc_write()")
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>