configs: move CONFIG_USB_EHCI_VF to Kconfig

Move CONFIG_USB_EHCI_VF to drivers/usb/host/Kconfig and update the one
and only user thereof being colibri_vf.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Igor Opaniuk <igor.opaniuk@toradex.com>
3 files changed