FROMGIT: maple_tree: introduce {mtree,mas}_lock_nested()

In some cases, nested locks may be needed, so {mtree,mas}_lock_nested is
introduced.  For example, when duplicating maple tree, we need to hold the
locks of two trees, in which case nested locks are needed.

At the same time, add the definition of spin_lock_nested() in tools for
testing.

Link: https://lkml.kernel.org/r/20231027033845.90608-3-zhangpeng.00@bytedance.com


Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

(cherry picked from commit b2472efe
https://git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

 mm-unstable)

Bug: 308042511
Change-Id: I06f0eb0a32a2f39b7842de08a0e5ce59895345c5
Signed-off-by: Suren Baghdasaryan <surenb@google.com>