CI: update valgrind to 3.17

our pmemcheck tool was recently rebased to upstream 3.17 version.
It contains at least few useful bug fixes, e.g.:
https://bugs.kde.org/show_bug.cgi?id=426144
https://bugs.kde.org/show_bug.cgi?id=407764

Author: lukaszstolarczuk

utils/docker/images/install-valgrind.sh

@@ -1,9 +1,9 @@
 #!/usr/bin/env bash
 # SPDX-License-Identifier: BSD-3-Clause
-# Copyright 2016-2020, Intel Corporation
+# Copyright 2016-2021, Intel Corporation
 
 #
-# install-valgrind.sh - installs valgrind for persistent memory
+# install-valgrind.sh - installs valgrind with pmemcheck
 #
 
 set -e
@@ -13,10 +13,10 @@ if [ "${SKIP_VALGRIND_BUILD}" ]; then
 	exit
 fi
 
-git clone --recursive https://github.com/pmem/valgrind.git
+git clone https://github.com/pmem/valgrind.git
 cd valgrind
-# pmem-3.15: Merge pull request #81 from marcinslusarz/pmem-3.15
-git checkout 09f75f69683d862f8456f75484fcdc0dc5508900
+# pmem-3.17: Merge pull request #85 from lukaszstolarczuk/pmem-3.17; 16.08.2021
+git checkout ff6f0f125f8e1b1a2a8615f2b14efeaf135ad01b
 
 ./autogen.sh
 ./configure --prefix=/usr