Add support for the Microsoft uuid attribute:

example:
struct __declspec(uuid("6d5140c1-7436-11ce-8034-00aa006009fa"))
test { };


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@122173 91177308-0d34-0410-b5e6-96231b3b80d8