maple_tree: arange64 node is not a leaf node

maple_tree: arange64 node is not a leaf node

mt_dump_arange64() only applies to an entry whose type is maple_arange_64,
in which mte_is_leaf() must return false.

Since mte_is_leaf() here is always false, we can remove this condition
check.

Link: https://lkml.kernel.org/r/20240826012422.29935-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>