HID: hid-ntrig: Prevent memory leak in ntrig_report_version()

HID: hid-ntrig: Prevent memory leak in ntrig_report_version()

Use a scope-based cleanup helper for the buffer allocated with kmalloc()
in ntrig_report_version() to simplify the cleanup logic and prevent
memory leaks (specifically the !hid_is_usb()-case one).

[jkosina@suse.com: elaborate on the actual existing leak]
Fixes: 185c926283da ("HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()")
Signed-off-by: Masami Ichikawa <masami256@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>