usb: xilinx: Add suspend resume support

Add suspend resume support. In the suspend udc is suspended
and it is set to ready at resume for it to be functional.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/20211118120143.1079-1-shubhrajyoti.datta@xilinx.com


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