edit std::collections::VecDeque docs

library/alloc/src/collections/vec_deque/mod.rs

@@ -1015,8 +1015,8 @@ pub fn shrink_to(&mut self, min_capacity: usize) {
     /// Shortens the deque, keeping the first `len` elements and dropping
     /// the rest.
     ///
-    /// If `len` is greater than the deque's current length, this has no
+    /// If `len` is greater or equal to the deque's current length, this has
-    /// effect.
+    /// no effect.
     ///
     /// # Examples
     ///