usb: typec: tcpm: cancel send discover hrtimer when unregister tcpm port

Like the state_machine_timer, we should also cancel possible pending
send discover identity hrtimer when unregister tcpm port.

Fixes: c34e85fa ("usb: typec: tcpm: Send DISCOVER_IDENTITY from dedicated work")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Li Jun <jun.li@nxp.com>
Link: https://lore.kernel.org/r/1622627829-11070-3-git-send-email-jun.li@nxp.com


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