Coverage of all built-in function overloads in >= 2.0 implementations

Overloads that take generic pointers were introduced in OpenCL C 2.0 for many built-in functions. When programs are built as OpenCL C 2.0 (or 3.0 on implementations that have support for the generic address space), these overloads are selected, when programs are built as OpenCL C 1.x (or 3.0 on implementations that don't support generic address space), overloads that take address-space-specific pointers are selected.

Prior to the branch unification in the CTS, the cl2x_trunk branches were always building programs as OpenCL C 2.0, which means that overloads taking address-space-specific pointers were never exercised. Since the move to a single branch, programs that can be built as OpenCL C 1.x are built as OpenCL C 1.x for compatibility with 1.x implementations, which means that the overloads that take a generic pointer are never exercised.

The CTS should exercise both overloads that take address-space-specific pointers and overloads that take generic pointers on implementations that can support both.

No files or tests are named in the issue. Start by locating the CTS coverage for built-in function overloads and the logic selecting OpenCL C versions or address spaces; done means exercising both address-space-specific and generic-pointer overloads on implementations that support both.

Written by the indexing model from the issue text.