Device attribute group @usb3_hardware_lpm_attr_group is merged by
add_power_attributes(), but it is not unmerged explicitly, fixed by
unmerging it in remove_power_attributes().

Fixes: 655fe4ef ("usbcore: add sysfs support to xHCI usb3 hardware LPM")
Cc: stable@vger.kernel.org
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/20240820-sysfs_fix-v2-1-a9441487077e@quicinc.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>