Fix a little think-o. In FileSpec::operator== we were trying to figure out...

Fix a little think-o.  In FileSpec::operator== we were trying to figure out whether the rhs file was resolved or not by comparing
the resolved version of the rhs FileSpec's directory name with the lhs FileSpec's directory name.  We really meant to compare it
with the rhs FileSpec's directory name...

<rdar://problem/12438838>

llvm-svn: 167349