This fixes the previously incorrect phy-mode for the OCEDO Ursus GMAC0.
See 62abbd587dc9 ("ath79: correct various phy-mode properties")
for more details.
Signed-off-by: David Bauer <mail@david-bauer.net>
(cherry picked from commit 7b137e9df920926dbd92f12450d9955c2759c92b)