tracing: Remove lookups from tracing_map hitcount

Lookups inflate the hitcount, making it essentially useless.  Only
inserts and updates should really affect the hitcount anyway, so
explicitly filter lookups out.

Link: http://lkml.kernel.org/r/c8d9dc39d269a8abf88bf4102d0dfc65deb0fc7f.1506105045.git.tom.zanussi@linux.intel.com



Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>