[SYCL][NFC] Fix doxygen annotation for graph method description (#14889)

Author: bader

sycl/source/detail/graph_impl.hpp

@@ -115,7 +115,7 @@ class node_impl {
   /// @param Prev Predecessor to \p node being added as successor.
   ///
   /// \p Prev should be a shared_ptr to an instance of this object, but can't
-  /// use a raw \p this pointer, so the extra \Prev parameter is passed.
+  /// use a raw \p this pointer, so the extra \p Prev parameter is passed.
   void registerSuccessor(const std::shared_ptr<node_impl> &Node,
                          const std::shared_ptr<node_impl> &Prev) {
     if (std::find_if(MSuccessors.begin(), MSuccessors.end(),