perf tools: Fix function declarations needed by parse-events.y

perf tools: Fix function declarations needed by parse-events.y

Patch "perf tools: Add location to pmu event terms" moved declarations
for parse_events_term__num() and parse_events_term__str() so that they
were no longer visible in parse-events.y. That can result in segfaults
as the arguments no longer need match the function prototype.

Move the declarations back, changing YYLTYPE pointers to
pointers-to-void because YYLTYPE is not generated until parse-events.y
is processed.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Link: http://lkml.kernel.org/r/1432040746-1755-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>