ARM: dts: stm32: Add bindings for FDCAN2 on AV96

Add FDCAN2 bindings to AV96 DT, the FDCAN2 is present on low-speed
expansion connector X6. This is disabled by default to match the
96boards specification though.
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>

arch/arm/boot/dts/stm32mp157a-avenger96.dts

@@ -414,6 +414,13 @@ &m_can1 {
 	status = "disabled";
 };
 
+&m_can2 {
+	pinctrl-names = "default", "sleep";
+	pinctrl-0 = <&m_can2_pins_a>;
+	pinctrl-1 = <&m_can2_sleep_pins_a>;
+	status = "disabled";
+};
+
 &pwr_regulators {
 	vdd-supply = <&vdd_io>;
 	vdd_3v3_usbfs-supply = <&vdd_usb>;