Move variable inside the ifdef block where it is only used

Change-Id: Ifa9e77b955cea26da6602d409a1c111f45f72587
Add line numbers to the OpenCL sources being logged

Makes __LINE__ numbers you have inserted in temporary printf() calls in the
(generated) OpenCL code more useful.

Change-Id: I6da5a6937b924c1378f7f0c25ab7e156b23e1b61