workaround for possible ROOT bug

In a unit test testORA_12 in package CondCore/ORA, in the ROOT6 IB, a call of TClass::GetClass("std::type_info") fails to find the class.  This is very strange, because this call works fine from the ROOT command line.  This may or may not be a ROOT bug.  I will write a JIRA ticket against ROOT for this issue.   In the meantime, this simple workaround avoids the problem, because TClass::GetClass(typeid(std::type_info)) works fine in the unit test.  Without this fix/workaround, this unit test will fail when the CMS specific ROOT patch (the TType class) is removed.

Please merge this request as soon as convenient.