bootmem: respect goal more likely

The old node-agnostic code tried allocating on all nodes starting from the
one with the lowest range.  alloc_bootmem_core retried without the goal if
it could not satisfy it and so the goal was only respected at all when it
happened to be on the first (lowest page numbers) node (or theoretically
if allocations failed on all nodes before to the one holding the goal).

Introduce a non-panicking helper that starts allocating from the node
holding the goal and falls back only after all thes tries failed, thus
moving the goal fallback code out of alloc_bootmem_core.

Make all other allocation functions benefit from this new helper.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>