Use the Meson8m2 specific USB2 PHY compatible string. The 3.10 vendor kernel has at least one known difference between Meson8 and Meson8m2: Meson8m2 sets the ACA_ENABLE bit while Meson8 doesn't. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Kevin Hilman <khilman@baylibre.com> Link: https://lore.kernel.org/r/20200515202520.1487514-1-martin.blumenstingl@googlemail.com