perf tools: Make target to generate self contained source tarball

Useful for when people want to try some version of the perf tools and don't
wants to download the kernel tarball.

Here is a session using this new target:

  [root@emilia linux-2.6-tip]# make help | grep -i perf
    perf-tar-src-pkg    - Build perf-2.6.35-rc1.tar source tarball
    perf-targz-src-pkg  - Build perf-2.6.35-rc1.tar.gz source tarball
    perf-tarbz2-src-pkg - Build perf-2.6.35-rc1.tar.bz2 source tarball
  [root@emilia linux-2.6-tip]# make perf-tarbz2-src-pkg
    TAR
  [root@emilia linux-2.6-tip]# ls -la perf-2.6.35-rc1.tar.bz2
  -rw-r--r-- 1 root root 295731 May 31 11:18 perf-2.6.35-rc1.tar.bz2
  [root@emilia linux-2.6-tip]# tar xf perf-2.6.35-rc1.tar.bz2
  [root@emilia linux-2.6-tip]# cd perf-2.6.35-rc1
  [root@emilia perf-2.6.35-rc1]# ls
  arch  HEAD  include  lib  tools
  [root@emilia perf-2.6.35-rc1]# cd tools/perf
  [root@emilia perf]# make -j9 2>&1 | tail
      CC arch/x86/util/dwarf-regs.o
      CC util/probe-finder.o
      CC util/newt.o
      CC util/scripting-engines/trace-event-perl.o
      CC scripts/perl/Perf-Trace-Util/Context.o
      CC perf.o
      CC builtin-help.o
      AR libperf.a
      LINK perf
  rm .perf.dev.null
  [root@emilia perf]# ./perf record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.262 MB perf.data (~11457 samples) ]
  [root@emilia perf]# ./perf report | head -12
  # Events: 6K cycles
  #
  # Overhead          Command       Shared Object  Symbol
  # ........  ...............  ..................  ......
  #
       4.73%             perf  [kernel.kallsyms]   [k] format_decode
       4.49%             perf  libc-2.12.so        [.] _IO_file_underflow_internal
       4.38%             init  [kernel.kallsyms]   [k] mwait_idle
       3.29%             perf  [kernel.kallsyms]   [k] vsnprintf
       2.38%             init  [kernel.kallsyms]   [k] sched_clock_local
       2.35%             init  [kernel.kallsyms]   [k] apic_timer_interrupt
       1.86%     sirq-timer/5  [kernel.kallsyms]   [k] find_busiest_group
  [root@emilia perf]#

Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20100528185357.GA28009@ghostprotocols.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>