tools/perf/build: Improve printout-of auto-detected features

tools/perf/build: Improve printout-of auto-detected features

Change the print-out of auto-detected features by making sure that
repeat invocations of 'make' when all features are successfully
detected do not produce the (rather lengthy) autodetection printout.

( When one or more features are missing then we still print out the
  feature detection table, to make sure people are aware of the
  resulting limitations. )

Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-qd8sMsshcjomxqx9bQcufmaa@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>