Staging: emxx_udc: emxx_udc: fixed coding style issue

fixed checkpatch.pl warning about 'Prefer 'unsigned int' to bare use of
'unsigned'

Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>