* Add program address space to data layout D37052
* Insert switch tables into the program memory address space D37053
* Require address space to be specified when creating functions D37054
8 [clang] Require address space to be specified when creating functions D37057
This adds initial support for letting targets specify which address
spaces their functions should reside in by default.
This is the first step towards placing functions into the correct
address space for Harvard architectures.