USB: cdc-acm: Add quirks for Yoga Book 9 14IAH10 INGENIC touchscreen

The Lenovo Yoga Book 9 14IAH10 (83KJ) has a composite USB device
(17EF:6161) that controls both touchscreens via a CDC ACM interface.
Interface 0 is a standard CDC ACM control interface, but interface 1
(the data interface) incorrectly declares vendor-specific class (0xFF)
instead of USB_CLASS_CDC_DATA. cdc-acm rejects the device at probe with
-EINVAL, leaving interface 0 unbound and EP 0x82 never polled.

With no consumer polling EP 0x82, the firmware's watchdog fires every
~20 seconds and resets the USB bus, producing a continuous disconnect/
reconnect loop that prevents the touchscreens from ever initialising.

Add two new quirk flags:

VENDOR_CLASS_DATA_IFACE: Bypasses the bInterfaceClass check in
acm_probe() that would otherwise reject the vendor-class data
interface with -EINVAL.

ALWAYS_POLL_CTRL: Submits the notification URB at probe() rather than
waiting for a TTY open. This keeps EP 0x82 polled at all times,
permanently suppressing the firmware watchdog. The URB is resubmitted
after port_shutdown() and on system resume. SET_CONTROL_LINE_STATE
(DTR|RTS) is sent at probe and after port_shutdown() to complete
firmware handshake.

Note: the firmware performs exactly 4 USB connect/disconnect cycles
(~19 s each) on every cold boot before stabilising. This is a fixed
firmware property; touch is available ~75-80 s after power-on.

Signed-off-by: Dave Carey <carvsdriver@gmail.com>
Cc: stable <stable@kernel.org>
Tested-by: Dave Carey <carvsdriver@gmail.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Link: https://patch.msgid.link/20260402182950.389016-1-carvsdriver@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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