perf evlist: Fix use of uninitialized variable
perf evlist: Fix use of uninitialized variable

Fixes valgrind complaint:
==1870== Syscall param write(buf) points to uninitialised byte(s)
==1870==    at 0x4E3F5B0: __write_nocancel (in /lib64/libpthread-2.14.90.so)
==1870==    by 0x449D7C: perf_evlist__start_workload (evlist.c:846)
==1870==    by 0x427BC1: cmd_record (builtin-record.c:561)
==1870==    by 0x419D72: run_builtin (perf.c:319)
==1870==    by 0x4195F2: main (perf.c:376)
==1870==  Address 0x7feffcdd7 is on thread 1's stack

Signed-off-by: David Ahern <b80c1600f604d3b0d768f26f90a76757e76005dd@gmail.com>
Cc: Frederic Weisbecker <e8a1bf9163cb25e93cfd6540f223b3872ea7ee55@gmail.com>
Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@kernel.org>
Cc: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Cc: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Link: http://lkml.kernel.org/r/1372793245-4136-3-git-send-email-b80c1600f604d3b0d768f26f90a76757e76005dd@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs