rust: kernel: clean up empty /// lines

Remove unnecessary empty `///` lines in the rust docs.

Suggested-by: Miguel Ojeda <[email protected]>
Link: Rust-for-Linux#1109
Signed-off-by: Hridesh MG <[email protected]>

Author: hrideshmg

rust/kernel/block/mq/request.rs

@@ -30,7 +30,6 @@ use core::{
 /// D) Request is owned by driver with more than one `ARef` in existence
 ///    (refcount > 2)
 ///
-///
 /// We need to track A and B to ensure we fail tag to request conversions for
 /// requests that are not owned by the driver.
 ///

rust/kernel/rbtree.rs

@@ -1031,7 +1031,6 @@ impl<K, V> Iterator for IterRaw<K, V> {
 
 /// A memory reservation for a red-black tree node.
 ///
-///
 /// It contains the memory needed to hold a node that can be inserted into a red-black tree. One
 /// can be obtained by directly allocating it ([`RBTreeNodeReservation::new`]).
 pub struct RBTreeNodeReservation<K, V> {