usb: Kconfig: Add Kconfigs entry USB_EHCI_ZYNQ

Add Kconfig entry config option for USB_EHCI_ZYNQ
and update the same to enable for all zynq boards
which supports USB

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 89580cc..5092251 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -85,6 +85,13 @@
 	  This driver supports combination of Chipidea USB controller
 	  and Synapsys USB PHY in host mode only.
 
+config USB_EHCI_ZYNQ
+	bool "Support for Xilinx Zynq on-chip EHCI USB controller"
+	depends on ARCH_ZYNQ
+	default y
+	---help---
+	  Enable support for Zynq on-chip EHCI USB controller
+
 config USB_EHCI_GENERIC
 	bool "Support for generic EHCI USB controller"
 	depends on OF_CONTROL