Merge pull request cms-sw#1669 from smuzaffar/IB/CMSSW_7_4_X/stable

updated xrootd tag: included cms-externals/xrootd#6

xrootd.spec

@@ -1,7 +1,7 @@
 ### RPM external xrootd 4.0.4
 ## INITENV +PATH LD_LIBRARY_PATH %i/lib64
 %define online %(case %cmsplatf in (*onl_*_*) echo true;; (*) echo false;; esac)
-%define tag 333bc986604f0e127ffd705be2abb491a1b443b7
+%define tag 0597009dfceb0b7614242a98e72e3f884f3271d3
 %define branch cms/v4.0.4
 %define github_user cms-externals
 Source: git+https://github.com/%github_user/xrootd.git?obj=%{branch}/%{tag}&export=%{n}-%{realversion}&output=/%{n}-%{realversion}.tgz