mm/readahead: fix kernel-doc notation

Fix kernel-doc notation in mm/readahead.c.

Change ":" to ";" so that it doesn't get treated as a doc section heading.
Move the comment block ending "*/" to a line by itself so that the text on
that last line is not lost (dropped).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/readahead.c

@@ -443,9 +443,10 @@ EXPORT_SYMBOL_GPL(page_cache_sync_readahead);
  *            pagecache pages
  *
  * page_cache_async_ondemand() should be called when a page is used which
- * has the PG_readahead flag: this is a marker to suggest that the application
+ * has the PG_readahead flag; this is a marker to suggest that the application
  * has used up enough of the readahead window that we should start pulling in
- * more pages. */
+ * more pages.
+ */
 void
 page_cache_async_readahead(struct address_space *mapping,
 			   struct file_ra_state *ra, struct file *filp,