Removed a parameter from handleAttrWithMessage to make it more consistent with other attribute handlers, as well as other attribute error messages.  Added missing test cases for the unavailable attribute, and updated the deprecated test case.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186578 91177308-0d34-0410-b5e6-96231b3b80d8