perf test: Allow multiple probes in record+script_probe_vfs_getname.sh

perf test: Allow multiple probes in record+script_probe_vfs_getname.sh

Sometimes when adding a kprobe by perf, it results in multiple probe
points, such as the following:

  # ./perf probe -l
    probe:vfs_getname    (on getname_flags:73@fs/namei.c with pathname)
    probe:vfs_getname_1  (on getname_flags:73@fs/namei.c with pathname)
    probe:vfs_getname_2  (on getname_flags:73@fs/namei.c with pathname)
  # cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/vfs_getname _text+5501804 pathname=+0(+0(%gpr31)):string
  p:probe/vfs_getname_1 _text+5505388 pathname=+0(+0(%gpr31)):string
  p:probe/vfs_getname_2 _text+5508396 pathname=+0(+0(%gpr31)):string

In this test, we need to record all of them and expect any of them in
the perf-script output, since it's not clear which one will be used for
the desired syscall:

  # perf stat -e probe:vfs_getname\* -- touch /tmp/nic

   Performance counter stats for 'touch /tmp/nic':

                31      probe:vfs_getname_2
                 0      probe:vfs_getname_1
                 1      probe:vfs_getname
       0.001421826 seconds time elapsed

       0.001506000 seconds user
       0.000000000 seconds sys

If the test relies only on probe:vfs_getname, it might easily miss the
relevant data.

Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
LPU-Reference: 20200722135845.29958-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>