usb: gadget: Move CONFIG_USB_GADGET_DUALSPEED to Kconfig

Move CONFIG_USB_GADGET_DUALSPEED option to Kconfig and
make all UDC controllers select USB_GADGET_DUALSPEED:
  - add next options to Kconfig selecting USB_GADGET_DUALSPEED:
    - USB_GADGET_ATMEL_USBA
    - USB_GADGET_DWC2_OTG
    - USB_DWC3
    - CI_UDC
  - make USB_MUSB_GADGET select USB_GADGET_DUALSPEED

While at it, make some related fixes:
  - remove DUALSPEED from configs that don't enable gadget support:
    - kwb.h
    - tseries.h
  - add missing USB_GADGET option to next configs:
    - novena_defconfig
    - pcm051_rev*_defconfig
    - xfi3_defconfig

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index bccf43e..da3ec2f 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -49,6 +49,8 @@
 
 source "drivers/usb/host/Kconfig"
 
+source "drivers/usb/dwc3/Kconfig"
+
 source "drivers/usb/musb-new/Kconfig"
 
 source "drivers/usb/emul/Kconfig"