hw/arm: ast2600: Wire up EHCI controllers

hw/arm: ast2600: Wire up EHCI controllers

Initialize EHCI controllers on AST2600 using the existing
TYPE_PLATFORM_EHCI. After this change, booting ast2600-evb
into Linux successfully instantiates a USB interface after
the necessary changes are made to its devicetree files.

ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
ehci-platform: EHCI generic platform driver
ehci-platform 1e6a3000.usb: EHCI Host Controller
ehci-platform 1e6a3000.usb: new USB bus registered, assigned bus number 1
ehci-platform 1e6a3000.usb: irq 25, io mem 0x1e6a3000
ehci-platform 1e6a3000.usb: USB 2.0 started, EHCI 1.00
usb usb1: Manufacturer: Linux 5.5.0-09825-ga0802f2d0ef5-dirty ehci_hcd
usb 1-1: new high-speed USB device number 2 using ehci-platform

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Message-id: 20200207174548.9087-1-linux@roeck-us.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>