drm/i915: Wedge the GPU if command parser setup fails

Commit 311a50e7

 ("drm/i915: Add support for mandatory cmdparsing")
introduced mandatory command parsing but setup failures were not
translated into wedging the GPU which was probably the intent.

Possible errors come in two categories. Either the sanity check on
internal tables has failed, which should be caught in CI unless an
affected platform would be missed in testing; or memory allocation failure
happened during driver load, which should be extremely unlikely but for
correctness should still be handled.

v2:
 * Tidy coding style. (Chris)

[airlied: cherry-picked to avoid rc1 base]
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 311a50e7

 ("drm/i915: Add support for mandatory cmdparsing")
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris.p.wilson@intel.com>
Reviewed-by: Chris Wilson <chris.p.wilson@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210302114213.1102223-1-tvrtko.ursulin@linux.intel.com
(cherry picked from commit 5a1a659762d35a6dc51047c9127c011303c77b7f)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>