Fix error in description of Megahertz
@@ -79,7 +79,7 @@ pub struct KiloHertz(pub u32);
/// Megahertz
///
-/// Create a frequency specified in kilohertz.
+/// Create a frequency specified in megahertz.
/// See also [`Hertz`] and [`KiloHertz`] for semantically correct ways of creating lower
/// frequencies.