acpi, nfit: quiet invalid block-aperture-region warnings

This state is already visible by userspace since the BLK region will not
be enabled, and it is otherwise benign as it usually indicates that the
DIMM is not configured.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

drivers/nvdimm/region_devs.c

@@ -833,7 +833,7 @@ int nd_blk_region_init(struct nd_region *nd_region)
 		return 0;
 
 	if (nd_region->ndr_mappings < 1) {
-		dev_err(dev, "invalid BLK region\n");
+		dev_dbg(dev, "invalid BLK region\n");
 		return -ENXIO;
 	}