usb: chipidea: udc: free pending TD at removal procedure

There is a pending TD which is not freed after request finishes,
we do this due to a controller bug. This TD needs to be freed when
the driver is removed. It prints below error message when unload
chipidea driver at current code:
"ci_hdrc ci_hdrc.0: dma_pool_destroy ci_hw_td, b0001000 busy"
It indicates the buffer at dma pool are still in use.

This commit will free the pending TD at driver's removal procedure,
it can fix the problem described above.

Acked-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>