Improve performance of debug trace output

[ywkaras]

Yahoo Prod is requesting that debug trace output use TSDbg() rather than TSDebug(). If support for obsolete release of TS is necessary, the following approach can be used:

#if defined(TSDbg)

const TSDbgCtl *dbg_ctl_yada = TSDbgCtlCreate("yada");
#define DBG_YADA(...) TSDbg(dbg_ctl_yada, __VA_ARGS__)

#else // For obsolete release of TS.

#define DBG_YADA(...) TSDebug("yada", __VA_ARGS__)

#endif