mm/page_alloc: fix a typo in comment about GFP flag

The GFP flags used to choose the zonelist is __GFP_THISNODE.

Let's change it to what exactly it should be.

Link: https://lkml.kernel.org/r/20240619010612.20740-3-richard.weiyang@gmail.com


Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>