perf test shell vfs_getname: Skip for tools built with NO_LIBDWARF=1

If that is the case, or if the required lib is not present, e.g.
elfutils-devel in Fedora systems, then just skip the tests requiring
DWARF analysis.

Before:

  # rpm -e elfutils-devel
  # perf test ping vfs_getname
  60: Use vfs_getname probe to get syscall args filenames   : FAILED!
  61: probe libc's inet_pton & backtrace it with ping       : Ok
  62: Check open filename arg using perf trace + vfs_getname: FAILED!
  63: Add vfs_getname probe to get syscall args filenames   : FAILED!
  #

After:

  # perf test vfs_getname
  60: Use vfs_getname probe to get syscall args filenames   : Skip
  62: Check open filename arg using perf trace + vfs_getname: Skip
  63: Add vfs_getname probe to get syscall args filenames   : Skip
  #

Then, reinstalling elfutils-devel, rebuilding the tool and running
again:

  # perf test vfs_getname
  60: Use vfs_getname probe to get syscall args filenames   : Ok
  62: Check open filename arg using perf trace + vfs_getname: Ok
  63: Add vfs_getname probe to get syscall args filenames   : Ok
  #

Reported-by: Kim Phillips <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Michael Petlan <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Thomas Richter <[email protected]>
Cc: Wang Nan <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/tests/shell/lib/probe_vfs_getname.sh

@@ -12,12 +12,12 @@ cleanup_probe_vfs_getname() {
 add_probe_vfs_getname() {
 	local verbose=$1
 	if [ $had_vfs_getname -eq 1 ] ; then
-               line=$(perf probe -L getname_flags | egrep 'result.*=.*filename;' | sed -r 's/[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*/\1/')
-               perf probe $verbose "vfs_getname=getname_flags:${line} pathname=result->name:string"
+		line=$(perf probe -L getname_flags |& egrep 'result.*=.*filename;' | sed -r 's/[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*/\1/')
+		perf probe $verbose "vfs_getname=getname_flags:${line} pathname=result->name:string"
 	fi
 }
 
 skip_if_no_debuginfo() {
-	add_probe_vfs_getname -v 2>&1 | grep -q "^Failed to find the path for kernel" && return 2
+	add_probe_vfs_getname -v 2>&1 | egrep -q "^(Failed to find the path for kernel|Debuginfo-analysis is not supported)" && return 2
 	return 1
 }