maple_tree: replace mas_logical_pivot() with mas_safe_pivot()

Replace mas_logical_pivot() with mas_safe_pivot() and drop
mas_logical_pivot() since it won't be used anymore.  We can do this since
now all nodes will have node limit pivot (if it is not full node).

Link: https://lkml.kernel.org/r/20230711035444.526-8-zhangpeng.00@bytedance.com


Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>