drm/i915: Consolidate error object printing

Leave all the pretty printing to userspace and simplify the error
capture to only have a single common object printer. It makes the kernel
code more compact, and the refactoring allows us to apply more complex
transformations like compressing the output.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-5-chris@chris-wilson.co.uk