USB: c67x00: Remove unused declaration c67x00_hcd_msg_received()

Commit e9b29ffc

 ("USB: add Cypress c67x00 OTG controller HCD driver")
declared but never implemented this.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20230825091518.22180-1-yuehaibing@huawei.com


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