mm/filemap.c: delete duplicated word

Drop the repeated word "the".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200801173822.14973-3-rdunlap@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/filemap.c

@@ -2885,7 +2885,7 @@ filler:
 	 * Case a, the page will be up to date when the page is unlocked.
 	 *    There is no need to serialise on the page lock here as the page
 	 *    is pinned so the lock gives no additional protection. Even if the
-	 *    the page is truncated, the data is still valid if PageUptodate as
+	 *    page is truncated, the data is still valid if PageUptodate as
 	 *    it's a race vs truncate race.
 	 * Case b, the page will not be up to date
 	 * Case c, the page may be truncated but in itself, the data may still