maple_tree: fix MAPLE_PARENT_RANGE32 and parent pointer docs

maple_tree: fix MAPLE_PARENT_RANGE32 and parent pointer docs

MAPLE_PARENT_RANGE32 should be 0x02 as a 32 bit node is indicated by the
bit pattern 0b010 which is the hex value 0x02.  There are no users
currently, so there is no associated bug with this wrong value.

Fix typo Note -> Node and replace x with b to indicate binary values.

Link: https://lkml.kernel.org/r/20250826151344.403286-1-sidhartha.kumar@oracle.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>