drm/i915: skip DRM_I915_LOW_LEVEL_TRACEPOINTS with NOTRACE

The order of the header files is important. If this header file is
included after tracepoint.h was included then the NOTRACE here becomes a
nop. Currently this happens for two .c files which use the tracepoitns
behind DRM_I915_LOW_LEVEL_TRACEPOINTS.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>