[PATCH] rust: rbtree: simplify finding `current` in `remove_current`

["Onur Özkan" <work@onurozkan.dev>]

The previous version used a verbose `match` to get
`current`, which may be slightly confusing at first
glance.

This change makes it shorter and more clearly expresses
the intent: prefer `next` if available, otherwise fall
back to `prev`.

Signed-off-by: Onur Özkan <work@onurozkan.dev>
---
 rust/kernel/rbtree.rs | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/rust/kernel/rbtree.rs b/rust/kernel/rbtree.rs
index 8d978c896747..8f1052552132 100644
--- a/rust/kernel/rbtree.rs
+++ b/rust/kernel/rbtree.rs
@@ -769,18 +769,10 @@ pub fn remove_current(self) -> (Option<Self>, RBTreeNode<K, V>) {
         // the tree cannot change. By the tree invariant, all nodes are valid.
         unsafe { bindings::rb_erase(&mut (*this).links, addr_of_mut!(self.tree.root)) };

-        let current = match (prev, next) {
-            (_, Some(next)) => next,
-            (Some(prev), None) => prev,
-            (None, None) => {
-                return (None, node);
-            }
-        };
-
         (
-            // INVARIANT:
-            // - `current` is a valid node in the [`RBTree`] pointed to by `self.tree`.
-            Some(Self {
+            next.or(prev).map(|current| Self {
+                // INVARIANT:
+                // - `current` is a valid node in the [`RBTree`] pointed to by `self.tree`.
                 current,
                 tree: self.tree,
             }),
--
2.50.0