mm: walk_memory_range(): fix typo in comment

Fix a typo "end_pft" in the comment of walk_memory_range().
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/memory_hotplug.c

@@ -1613,7 +1613,7 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 /**
  * walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
  * @start_pfn: start pfn of the memory range
- * @end_pfn: end pft of the memory range
+ * @end_pfn: end pfn of the memory range
  * @arg: argument passed to func
  * @func: callback for each memory section walked
  *