cxl/region: Fix missing probe failure

cxl/region: Fix missing probe failure

commit bf3e5da8cb43a671b32fc125fa81b8f6a3677192 upstream.

cxl_region_probe() allows for regions not in the 'commit' state to be
enabled. Fail probe when the region is not committed otherwise the
kernel may indicate that an address range is active when none of the
decoders are active.

Fixes: 810bf10060bc ("cxl/region: Add region driver boiler plate")
Cc: <stable@vger.kernel.org>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/166993220462.1995348.1698008475198427361.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>