perf intel-pt: Re-factor TIP cases in intel_pt_walk_to_ip

To make it easier to add new code for different TIP cases, separate each
case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190520113728.14389-11-adrian.hunter@intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>