usb: mtu3: mtu3_trace: Function headers are not suitable for kerneldoc

Kerneldoc headers should only be used to document functions and data
structures.

Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: linux-mediatek@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200715093209.3165641-4-lee.jones@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>