Several i.MX boards (all i.MX6 boards) need to do some adjustments
to phy registers. If barebox itself does not use network, networking
won't work in the kernel if the kernel does not have the fixups. Connect
the phy at probe time so that these tweaks are done during probe so that
the kernel works without phy register tweaks. Also this has the effect
that the phy device is present and introspectable without doing fake
network transfers beforehand.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>