sun6i: Add gmac support for sun6i boards

Hookup the gmac found on the sun6i / A31 SoCs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
sunxi: Use "usb start" rather then "run usb_init" for preboot with usb-kbd

In an effort to avoid usb getting scanned twice when using an usb keyboard,
and booting from usb, I've set preboot to "run usb_init" in the
CONFIG_USB_KEYBOARD patch.

This is wrong however, as it causes usb to not be scanned (and the keyboard to
not be found) if an "env save" is done, since then the env
contains usb_need_init=false.

This commit fixes this by changing the preboot value to "usb start", so that
usb gets scanned for a keyboard unconditionally when usb-keyboard support is
enabled.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
config_distro_bootcmd.h: Allow user to indicate that usb is inited in preboot

When using usb-keyboard support, typically usb will already get started from
preboot. In this case doing it again in the bootcmd is undesirable.

Allow the user of config_distro_bootcmd to indicate that usb is inited in
preboot through the user setting BOOTENV_PREBOOT_INITS_USB.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
sunxi: Avoid usb getting scanned twice when using usb kbd + usb boot

Use the new BOOTENV_PREBOOT_INITS_USB define to avoid usb being scanned twice
when using usb kbd + usb boot.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>