Fix rustfmt failing

Author: JanekGraff

src/lib.rs

@@ -41,6 +41,8 @@ pub mod dac;
 #[cfg(feature = "device-selected")]
 pub mod delay;
 #[cfg(feature = "device-selected")]
+pub mod flash;
+#[cfg(feature = "device-selected")]
 pub mod gpio;
 #[cfg(feature = "device-selected")]
 pub mod i2c;
@@ -53,15 +55,13 @@ pub mod rcc;
 #[cfg(feature = "device-selected")]
 pub mod serial;
 #[cfg(feature = "device-selected")]
+pub mod signature;
+#[cfg(feature = "device-selected")]
 pub mod spi;
 #[cfg(feature = "device-selected")]
 pub mod time;
 #[cfg(feature = "device-selected")]
 pub mod timers;
-#[cfg(feature = "device-selected")]
-pub mod flash;
-#[cfg(feature = "device-selected")]
-pub mod signature;
 #[cfg(any(
     feature = "stm32f031",
     feature = "stm32f051",