docbook: fix fatal filename error

Fix docbook fatal error:

docproc: block/blktrace.c: No such file or directory

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index 58c1945..d6ac5d6 100644
--- a/Documentation/DocBook/kernel-api.tmpl
+++ b/Documentation/DocBook/kernel-api.tmpl
@@ -259,7 +259,7 @@
 !Eblock/blk-tag.c
 !Iblock/blk-tag.c
 !Eblock/blk-integrity.c
-!Iblock/blktrace.c
+!Ikernel/trace/blktrace.c
 !Iblock/genhd.c
 !Eblock/genhd.c
   </chapter>