mm: kmemleak: add rbtree and store physical address for objects allocated with PA

mm: kmemleak: add rbtree and store physical address for objects allocated with PA

Add object_phys_tree_root to store the objects allocated with physical
address.  Distinguish it from object_tree_root by OBJECT_PHYS flag or
function argument.  The physical address is stored directly in those
objects.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Patrick Wang <[email protected]>
Suggested-by: Catalin Marinas <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Cc: Yee Lee <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>