loplugin:unreffun -- Wrap opencl-only functions in appropriate ifdef.
loplugin:unreffun -- Wrap opencl-only functions in appropriate ifdef.

This section is only needed if we have opencl enabled, hence we should
wrap it in HAVE_FEATURE_OPENCL.

Change-Id: I5ec479d7c1739fcb8baf0936104425b515b6a843

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core