perf probe: Fix to add missed brace around if block

The commit 75186a9b (perf probe: Fix to show lines of sys_ functions
correctly) introduced a bug by a missed brace around if block. This
fixes to add it.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 75186a9b ("perf probe: Fix to show lines of sys_ functions correctly")
Link: http://lkml.kernel.org/r/20150812215541.9088.62425.stgit@localhost.localdomain


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>