usb: typec: ucsi: Add conditional dependency on USB role switch

Preventing the driver from being built-in when USB Role
Switch Class is being build as module. That fixes a
potential undefined reference error.

Fixes: 89795852

 ("usb: typec: ucsi: Add support for USB role switch")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210119083405.18325-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>