mm/filemap.c: fix minor typo

Link: http://lkml.kernel.org/r/20190304155240.19215-1-ldufour@linux.ibm.comSigned-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/filemap.c

@@ -1446,7 +1446,7 @@ pgoff_t page_cache_next_miss(struct address_space *mapping,
 EXPORT_SYMBOL(page_cache_next_miss);
 
 /**
- * page_cache_prev_miss() - Find the next gap in the page cache.
+ * page_cache_prev_miss() - Find the previous gap in the page cache.
  * @mapping: Mapping.
  * @index: Index.
  * @max_scan: Maximum range to search.