tools/liblockdep: Use the rbtree header provided by common tools headers

Recent changes to rbtree.h may break compilation. There is no
reason to use a liblockdep specific header to begin with, so
we'll use the one shared with all other tools/.

Signed-off-by: Sasha Levin <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

tools/lib/lockdep/preload.c

···
 #include <stdlib.h>
 #include <sysexits.h>
 #include "include/liblockdep/mutex.h"
-#include "../../../include/linux/rbtree.h"
+#include "../../include/linux/rbtree.h"
 
 /**
  * struct lock_lookup - liblockdep's view of a single unique lock

tools/lib/lockdep/uinclude/linux/rbtree.h

···
-#include "../../../include/linux/rbtree.h"