drm/i915/uc: Abort early on uc_init failure

Now that we can differentiate wants vs uses GuC/HuC, intel_uc_init is
restricted to running only if we have successfully fetched the required
blob(s) and are committed to using the microcontroller(s).
The only remaining thing that can go wrong in uc_init is the allocation
of GuC/HuC related objects; if we get such a failure better to bail out
immediately instead of wedging later, like we do for e.g.
intel_engines_init, since without objects we can't use the HW, including
not being able to attempt the firmware load.

While at it, remove the unneeded fw_cleanup call (this is handled
outside of gt_init) and add a probe failure injection point for testing.
Also, update the logs for <g/h>uc_init failures to probe_failure() since
they will cause the driver load to fail.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Fernando Pacheco <fernando.pacheco@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-8-daniele.ceraolospurio@intel.com