configs: Migrate all of the existing USB symbols, except fastboot

This syncs all of the currently Kconfig'd symbols out of the headers and
into the defconfig files.  This has two exceptions, first am335x_evm
needs to be converted to DM in SPL and then it can stop undef'ing
CONFIG_DM_USB.  Leaving this as-is results in a build failure, and
without work, run time failure.  The other case is am43xx_evm.h and in
turn am43xx_evm_usbhost_boot.  The problem here is that we need DWC3 USB
host mode in SPL, but still desire to have gadget mode in U-Boot proper.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/nitrogen6q_defconfig b/configs/nitrogen6q_defconfig
index 44f5398..9e185cc 100644
--- a/configs/nitrogen6q_defconfig
+++ b/configs/nitrogen6q_defconfig
@@ -41,6 +41,7 @@
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
 CONFIG_USB_KEYBOARD=y
+CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP=y
 CONFIG_USB_GADGET=y
 CONFIG_CI_UDC=y
 CONFIG_USB_GADGET_DOWNLOAD=y