drm/i915/guc: use probe_error log for CT enablement failure

We have a couple of failure injection points in the CT enablement path,
so we need to use i915_probe_error() to select the appropriate log level.
A new macro (CT_PROBE_ERROR) has been added to the set of CT logging
macros to be used in this scenario and upcoming ones.

While adding the new macros, fix the underlying logging mechanics used
by the existing ones (DRM_DEV_* -> drm_*) and move the inlines to
before they're used inside the macros.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603051630.2635-3-matthew.brost@intel.com