perf probe: List probes with line number and file name

Improve --list to show current exist probes with line number and
file name. This enables user easily to check which line is
already probed.

for example:

 ./perf probe --list
 probe:vfs_read       (on vfs_read:8@linux-2.6-tip/fs/read_write.c)

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220619.32050.48702.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/util/probe-finder.h

@@ -20,6 +20,10 @@ static inline int is_c_varname(const char *name)
 extern int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
 				    struct kprobe_trace_event **tevs);
 
+/* Find a perf_probe_point from debuginfo */
+extern int find_perf_probe_point(int fd, unsigned long addr,
+				 struct perf_probe_point *ppt);
+
 extern int find_line_range(int fd, struct line_range *lr);
 
 #include <dwarf.h>