perf test vfs_getname: Look for alternative line where to collect the pathname

The getname_flags() routine changed recently and thus the place where we
were getting the pathname is not probeable anymore, albeit still
present, so use the next line for that, before:

  root@number:/home/acme/git/perf-tools-next# perf test vfs_getname
   91: Add vfs_getname probe to get syscall args filenames             : FAILED!
   93: Use vfs_getname probe to get syscall args filenames             : FAILED!
  126: Check open filename arg using perf trace + vfs_getname          : FAILED!
  root@number:/home/acme/git/perf-tools-next#

Now tests 91 and 126 are passing, some more investigation is needed for
test 93, that continues to fail.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>