clBuildProgram.c: Use the new subdevice macros
clBuildProgram.c: Use the new subdevice macros

This (and the following commits) try to make pocl keep
internally only the "real" devices, while the runtime API
still accepts any subdevice. Command queues are an exception,
because we need the subdevice to schedule the proper # of threads.

vkorhonen/pocl,vkorhonen/pocl,pocl/pocl,Oblomov/pocl,pavanky/pocl,pavanky/pocl,pocl/pocl,jrprice/pocl,pocl/pocl,jrprice/pocl,franz/pocl,rjodin/pocl,Oblomov/pocl,vkorhonen/pocl,vkorhonen/pocl,franz/pocl,jrprice/pocl,pocl/pocl,rjodin/pocl,dsandersimgtec/pocl,pavanky/pocl,Oblomov/pocl,franz/pocl,pavanky/pocl,pocl/pocl,dsandersimgtec/pocl,Oblomov/pocl,dsandersimgtec/pocl,franz/pocl,Oblomov/pocl,rjodin/pocl,dsandersimgtec/pocl,jrprice/pocl,franz/pocl,rjodin/pocl