Add HAL for i2c3 available on the stm32l4s5 family.

Author: Bob McWhirter

src/i2c.rs

@@ -325,6 +325,7 @@ hal! {
 
 use crate::gpio::gpioa::{PA10, PA9};
 use crate::gpio::gpiob::{PB10, PB11, PB6, PB7};
+use crate::gpio::gpioc::{PC0, PC1};
 
 pins!(I2C1, AF4,
     SCL: [PA9, PB6],
@@ -340,3 +341,13 @@ pins!(I2C1, AF4, SCL: [PB8], SDA: [PB9]);
 
 #[cfg(any(feature = "stm32l4x1", feature = "stm32l4x6"))]
 pins!(I2C2, AF4, SCL: [PB13], SDA: [PB14]);
+
+#[cfg(feature = "stm32l4x5")]
+pins!(I2C3, AF4, SCL: [PC0], SDA: [PC1]);
+
+#[cfg(feature = "stm32l4x5")]
+use crate::stm32::I2C3;
+#[cfg(feature = "stm32l4x5")]
+hal! {
+    I2C3: (i2c3, i2c3en, i2c3rst),
+}