maple_tree: remove pointer to pointer use in mas_alloc_nodes()

There is a more direct and cleaner way of implementing the same functional
code.  Remove the confusing and unnecessary use of pointers here.

Link: https://lkml.kernel.org/r/20221026151241.4031117-1-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

lib/maple_tree.c

@@ -1209,7 +1209,6 @@ static inline void mas_push_node(struct ma_state *mas, struct maple_node *used)
 static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp)
 {
 	struct maple_alloc *node;
-	struct maple_alloc **nodep = &mas->alloc;
 	unsigned long allocated = mas_allocated(mas);
 	unsigned long success = allocated;
 	unsigned int requested = mas_alloc_req(mas);
@@ -1263,8 +1262,7 @@ static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp)
 			node->node_count--;
 
 		success += count;
-		nodep = &node->slot[0];
-		node = *nodep;
+		node = node->slot[0];
 		requested -= count;
 	}
 	mas->alloc->total = success;