rust: alloc: add Vec to prelude

Now that we removed `VecExt` and the corresponding includes in
prelude.rs, add the new kernel `Vec` type instead.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

Author: Danilo Krummrich

rust/kernel/prelude.rs

@@ -14,7 +14,7 @@
 #[doc(no_inline)]
 pub use core::pin::Pin;
 
-pub use crate::alloc::{flags::*, Box, KBox, KVBox, KVVec, KVec, VBox, VVec};
+pub use crate::alloc::{flags::*, Box, KBox, KVBox, KVVec, KVec, VBox, VVec, Vec};
 
 #[doc(no_inline)]
 pub use macros::{module, pin_data, pinned_drop, vtable, Zeroable};