drm/i915: Record more information about the hanging contexts

Include extra information such as the user_handle and hw_id so that
userspace can identify which of their contexts hung, useful if they are
performing self-diagnositics.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170129092433.10483-1-chris@chris-wilson.co.uk


Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>