renderer: Remove unused error from CoglRendererError
renderer: Remove unused error from CoglRendererError

This type is not documented and is experimental. We don't use
COGL_RENDERER_ERROR_NOT_FOUND and it's pretty vague anyway, just remove
it.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit ffa78534616547b9bd4cd5c0ade8fdc039a2b977)

Distrotech/cogl,Distrotech/cogl,Distrotech/cogl,Distrotech/cogl