maple_tree: remove the redundant code

The macros CONFIG_DEBUG_MAPLE_TREE_VERBOSE no one uses, functions
mas_dup_tree() and mas_dup_store() are not implemented, just function
declaration, so drop it.

Link: https://lkml.kernel.org/r/20221221060058.609003-6-vernon2gm@gmail.com


Signed-off-by: Vernon Yang <vernon2gm@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>