xilinx_emacps.c: Attach gmii2rgmii before connecting to actual PHY

Connecting to the PHY starts the state machine and may trigger the
callback. The callback requires the gmii2rgmii interface if that is
being used, so the gmii2rgmii phy must be initialized first.

Instead of "of_phy_connect" use "of_phy_attach", because no state
machine should be started from this phy and it is only used to
communicate settings from the real PHY to the gmii2rgmii logic.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
net/phy: micrel: Disable asymmetric pause for KSZ9031

Our KSZ9031 appears to suffer from the same hardware bug as described
for the KSZ9021 in commit 32fcafbcd1c9f6c7013016a22a5369b4acb93577,
you have to unplug the cable and plug it back to get it to work.

Remove the SUPPORTED_Asym_Pause flag for the KSZ9031 to fix this.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
topic-miami: Configure ethernet using gmii2rgmii PL block

Provide the information to get the emacs to run via PL, using a
GMII to RGMII conversion block in logic.

Remove obsolete information from the zynq.dtsi ethernet node.