ARM: dts: stm32: Repair ethernet operation on AV96

ARM: dts: stm32: Repair ethernet operation on AV96

The AV96 RGMII uses different pinmux for ETH_RGMII_TXD0, ETH_RGMII_RXD2
and ETH_RGMII_TX_CTL. Use the correct pinmux to make ethernet operational.

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>