perf tools: Remove verbose build messages for the python binding

Also now it builds it in a well known location:

[acme@felicio linux]$ rm -rf ../build/perf/
[acme@felicio linux]$ mkdir ../build/perf
[acme@felicio linux]$ make -j2 O=~acme/git/build/perf -C tools/perf/
<SNIP>
[acme@felicio linux]$ ls -la ../build/perf/python/
total 152
-rwxrwxr-x 1 acme acme 147957 Feb  1 14:56 perf.so
drwxrwxr-x 3 acme acme     17 Feb  1 14:56 temp
[acme@felicio linux]$

[root@felicio ~]# strip ~acme/git/build/perf/python/perf.so
[root@felicio ~]# ls -la ~acme/git/build/perf/python/perf.so
-rwxrwxr-x 1 acme acme 46264 Feb  1 14:58 /home/acme/git/build/perf/python/perf.so

[root@felicio ~]# export PYTHONPATH=~acme/git/build/perf/python/
[root@felicio ~]# ~acme/git/linux/tools/perf/python/twatch.py
cpu:  0, pid: 7751, tid: 7751 { type: exit, pid: 7751, ppid: 7751, tid: 7751, ptid: 7751, time: 54562393512356}
cpu:  0, pid: 13700, tid: 13700 { type: fork, pid: 7756, ppid: 13700, tid: 7756, ptid: 13700, time: 54562393746739}
cpu:  1, pid: 7756, tid: 7756 { type: fork, pid: 7757, ppid: 7756, tid: 7757, ptid: 7756, time: 54562394246152}
cpu:  1, pid: 7757, tid: 7757 { type: comm, pid: 7757, tid: 7757, comm: awk }
cpu:  1, pid: 7757, tid: 7757 { type: exit, pid: 7757, ppid: 7757, tid: 7757, ptid: 7757, time: 54562395456813}

Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>