maple_tree: calculate new_end when needed

Patch series "Following cleanup after introduce mas_wr_store_type()", v2.

Patch 1 postpone new_end calculation when needed.
Patch 2 removes a unnecessary sanity check in mas_wr_slot_store().


This patch (of 2):

For wr_exact_fit/wr_new_root, we don't need to calculate new_end.

Let's postpone it until necessary.

Link: https://lkml.kernel.org/r/20241017015809.23392-1-richard.weiyang@gmail.com
Link: https://lkml.kernel.org/r/20241017015809.23392-2-richard.weiyang@gmail.com


Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>