Move tp.[ch] to lib/

It's just helper code, not fio core.

Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/iolog.c b/iolog.c
index 0d07b0e..9506705 100644
--- a/iolog.c
+++ b/iolog.c
@@ -18,7 +18,7 @@
 #include "verify.h"
 #include "trim.h"
 #include "filelock.h"
-#include "tp.h"
+#include "lib/tp.h"
 
 static const char iolog_ver2[] = "fio version 2 iolog";