memblock/nobootmem: remove unneeded code from alloc_bootmem_node_high()

memblock/nobootmem: remove unneeded code from alloc_bootmem_node_high()

The bootmem wrapper with memblock supports top-down now, so we no longer
need this trick.

Signed-off-by: Yinghai LU <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Olaf Hering <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Lucas De Marchi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>