mark raw_vec::ptr with inline

Author: andjo403

library/alloc/src/raw_vec.rs

@@ -220,6 +220,7 @@ impl<T, A: AllocRef> RawVec<T, A> {
     /// Gets a raw pointer to the start of the allocation. Note that this is
     /// `Unique::dangling()` if `capacity == 0` or `T` is zero-sized. In the former case, you must
     /// be careful.
+    #[inline]
     pub fn ptr(&self) -> *mut T {
         self.ptr.as_ptr()
     }