update root 6.08

cherry-picked following commits to fix TF1 and out-of-order lock problems
- root-project/root@af59257
- root-project/root@6eb83c4
- root-project/root@5ff21c9

root.spec

@@ -1,7 +1,7 @@
 ### RPM lcg root 6.08.06
 ## INITENV +PATH PYTHONPATH %{i}/lib
 ## INITENV SET ROOTSYS %{i}
-%define tag 8702101c0f3675b1a048df0154b36ec3f1e7ff8d
+%define tag 18ebc20755fc6edb871dc2ba156ee046d615a084
 %define branch cms/a463592
 %define github_user cms-sw
 Source: git+https://github.com/%{github_user}/root.git?obj=%{branch}/%{tag}&export=%{n}-%{realversion}&output=/%{n}-%{realversion}-%{tag}.tgz