Convert CONFIG_USB_XHCI_OMAP to Kconfig

This converts the following to Kconfig:
   CONFIG_USB_XHCI_OMAP

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/cm_t43_defconfig b/configs/cm_t43_defconfig
index eea9a74..45b41d3 100644
--- a/configs/cm_t43_defconfig
+++ b/configs/cm_t43_defconfig
@@ -91,3 +91,4 @@
 CONFIG_USB=y
 CONFIG_USB_XHCI_HCD=y
 CONFIG_USB_XHCI_DWC3=y
+CONFIG_USB_XHCI_OMAP=y