[FS#1428] ramips: mt7620n: NEXX WT3020 switch detection broken

[LEDE Bugs]

The following task has a new comment added:

FS#1428 - ramips: mt7620n: NEXX WT3020 switch detection broken
User who did this - Mathias Kresin (mkresin)

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Thanks a lot for the bootlog.

Would you please apply https://www.kresin.me/files/mt7620n_mdio.patch to an unmodified tree and check if it fixes the issue.

It might be that I introduced more issues with the mentioned commits and I would like to fix all of them.
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More information can be found at the following URL:
https://bugs.openwrt.org/index.php?do=details&task_id=1428#comment4461