doc: library versions need to be bumped in version.h

doc/developer.texi

@@ -281,7 +281,7 @@ send a reminder by email. Your patch should eventually be dealt with.
     AVInputFormat/AVOutputFormat struct?
 @item
     Did you bump the minor version number (and reset the micro version
-    number) in @file{avcodec.h} or @file{avformat.h}?
+    number) in @file{libavcodec/version.h} or @file{libavformat/version.h}?
 @item
     Did you register it in @file{allcodecs.c} or @file{allformats.c}?
 @item