usb: xhci: Add input slot context in xhci_set_configuration()

A valid input slot context for a 'configure endpoint' command requires
the 'Context Entries' field to be initialized to the index of the last
valid endpoint context that is defined by the target configuration. We
set up the 'Context Entries' field, but we forget to include the input
slot context in the input control context 'Add Context flags' bitmap.
So xHC will simply ignore input slot context and continue using its own
which contains old information of the device.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>