usb: raw-gadget: fix handling of dual-direction-capable endpoints

usb: raw-gadget: fix handling of dual-direction-capable endpoints

Under dummy_hcd, every available endpoint is *either* IN or OUT capable.
But with some real hardware, there are endpoints that support both IN and
OUT. In particular, the PLX 2380 has four available endpoints that each
support both IN and OUT.

raw-gadget currently gets confused and thinks that any endpoint that is
usable as an IN endpoint can never be used as an OUT endpoint.

Fix it by looking at the direction in the configured endpoint descriptor
instead of looking at the hardware capabilities.

With this change, I can use the PLX 2380 with raw-gadget.

Fixes: 36f4122a898f ("usb: gadget: add raw-gadget interface")
Cc: stable <stable@vger.kernel.org>
Tested-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20220126205214.2149936-1-jannh@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>