CPU-Dispatch- Fix type of a member function, prevent deferrals

The member type creation for a cpu-dispatch function was not correctly
including the 'this' parameter, so ensure that the type is properly
determined. Also, disable defer in the cases of emitting the functoins,
as it can end up resulting in the wrong version being emitted.

Change-Id: I0b8fc5e0b0d1ae1a9d98fd54f35f27f6e5d5d083
llvm-svn: 345838