mm/memblock: correct doc for function

Change "max_addr" to "end" for less confusion in
memblock_alloc_range_nid comments.

Link: http://lkml.kernel.org/r/20191113051822.3296-1-ruansy.fnst@cn.fujitsu.com
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memblock.c

@@ -1321,7 +1321,7 @@ __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
  *
  * The allocation is performed from memory region limited by
- * memblock.current_limit if @max_addr == %MEMBLOCK_ALLOC_ACCESSIBLE.
+ * memblock.current_limit if @end == %MEMBLOCK_ALLOC_ACCESSIBLE.
  *
  * If the specified node can not hold the requested memory the
  * allocation falls back to any node in the system