This patch refactors the arm page table dumping code,
so multiple tables may be registered with the framework.

This patch refers below commits of arm64.
(4674fdb9 ("arm64: mm: dump: make page table dumping reusable"))
(4ddb9bf8 ("arm64: dump: Make ptdump debugfs a separate option"))
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>