ARM: dts: stm32: Add alternate pinmux for SPI2 pins

Add another mux option for SPI2 pins, this is used on DRC Compact board.

Signed-off-by: Marek Vasut <[e-mail]>
Cc: Alexandre Torgue <[e-mail]>
Cc: [e-mail]
To: [e-mail]
Signed-off-by: Alexandre Torgue <[e-mail]>

arch/arm/boot/dts/stm32mp15-pinctrl.dtsi

···
 		};
 	};
 
+	spi2_pins_b: spi2-1 {
+		pins1 {
+			pinmux = <STM32_PINMUX('I', 1, AF5)>, /* SPI2_SCK */
+				 <STM32_PINMUX('I', 3, AF5)>; /* SPI2_MOSI */
+			bias-disable;
+			drive-push-pull;
+			slew-rate = <1>;
+		};
+
+		pins2 {
+			pinmux = <STM32_PINMUX('I', 2, AF5)>; /* SPI2_MISO */
+			bias-disable;
+		};
+	};
+
 	spi4_pins_a: spi4-0 {
 		pins {
 			pinmux = <STM32_PINMUX('E', 12, AF5)>, /* SPI4_SCK */