perf probe: Fix need_dwarf flag if lazy matching is used

Set need_dwarf if lazy matching pattern is specified, because
lazy matching requires real source path for which we must use
debuginfo.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100312232224.2017.54550.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>