perf trace: Introduce trace__btf_scnprintf()

perf trace: Introduce trace__btf_scnprintf()

To have a central place that will look at the BTF type and call the
right scnprintf routine or return zero, meaning BTF pretty printing
isn't available or not implemented for a specific type.

Signed-off-by: Howard Chu <howardchu95@gmail.com>
Tested-by: Howard Chu <howardchu95@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240624181345.124764-8-howardchu95@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>