Remove everything marked deprecated

emath/src/rot2.rs

@@ -33,11 +33,6 @@ impl Rot2 {
     /// The identity rotation: nothing rotates
     pub const IDENTITY: Self = Self { s: 0.0, c: 1.0 };
 
-    #[deprecated = "Use Rot2::IDENTITY"]
-    pub fn identity() -> Self {
-        Self::IDENTITY
-    }
-
     /// A 𝞃/4 = 90° rotation means rotating the X axis to the Y axis.
     pub fn from_angle(angle: f32) -> Self {
         let (s, c) = angle.sin_cos();