Commit a7be6e5a ("mm: drop useless local parameters of
__register_one_node()") removed the last user of parent_node().

The parent_node() macro in SPARC64 platform is unnecessary.

Remove it for cleanup.

Link: http://lkml.kernel.org/r/1504234599-29533-6-git-send-email-douly.fnst@cn.fujitsu.comSigned-off-by: NDou Liyang <douly.fnst@cn.fujitsu.com>
Reported-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>