This patch adds initial support for detecting type of launched kernel.

If there is a parallel pragma inside target region, then we assume
that we have SPMD kernel.

This assumption is not valid for target regions for which parallel region
does not cover the whole target region.

Proposed implementation of the new device OpenMP functions relies on
internal functions which are not used in current version of the OpenMP
runtime.

TODO: Modify CodeExtractor so that it will take alloca address
space from constructor parameter

TODO: Add missing definitions for the newwq OpenMP device RTL functions
TODO: Add missing attributes for the new OpenMP device RTL functions