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/configs/am335x_boneblack_defconfig b/configs/am335x_boneblack_defconfig
index 8b6fa20..46ac471 100644
--- a/configs/am335x_boneblack_defconfig
+++ b/configs/am335x_boneblack_defconfig
@@ -18,5 +18,6 @@
 CONFIG_SPI_FLASH_WINBOND=y
 CONFIG_SYS_NS16550=y
 CONFIG_USB=y
+CONFIG_USB_MUSB_GADGET=y
 CONFIG_USB_GADGET=y
 CONFIG_OF_LIBFDT=y