maple_tree: remove redundant __GFP_NOWARN

Commit 16f5dfb ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made
GFP_NOWAIT implicitly include __GFP_NOWARN.

Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g.,
`GFP_NOWAIT | __GFP_NOWARN`) is now redundant.  Let's clean up these
redundant flags across subsystems.

No functional changes.

Link: https://lkml.kernel.org/r/20250804125657.482109-1-rongqianfeng@vivo.com
Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

Author: qianfengrong

lib/maple_tree.c

@@ -1344,11 +1344,11 @@ static void mas_node_count_gfp(struct ma_state *mas, int count, gfp_t gfp)
  * @mas: The maple state
  * @count: The number of nodes needed
  *
- * Note: Uses GFP_NOWAIT | __GFP_NOWARN for gfp flags.
+ * Note: Uses GFP_NOWAIT for gfp flags.
  */
 static void mas_node_count(struct ma_state *mas, int count)
 {
-	return mas_node_count_gfp(mas, count, GFP_NOWAIT | __GFP_NOWARN);
+	return mas_node_count_gfp(mas, count, GFP_NOWAIT);
 }
 
 /*