tools/testing/nvdimm: Fix fallthrough warning

Use the expected 'fall through' designation to fix:

tools/testing/nvdimm/test/nfit.c: In function ‘nd_intel_test_finish_query’:
tools/testing/nvdimm/test/nfit.c:433:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
fw->state = FW_STATE_UPDATED;
~~~~~~~~~~^~~~~~~~~~~~~~~~~~
tools/testing/nvdimm/test/nfit.c:435:2: note: here
case FW_STATE_UPDATED:
^~~~

Reviewed-by: Vishal Verma <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Dan Williams <[e-mail]>

tools/testing/nvdimm/test/nfit.c

···
 			dev_dbg(dev, "%s: still verifying\n", __func__);
 			break;
 		}
-
 		dev_dbg(dev, "%s: transition out verify\n", __func__);
 		fw->state = FW_STATE_UPDATED;
-		/* we are going to fall through if it's "done" */
+		/* fall through */
 	case FW_STATE_UPDATED:
 		nd_cmd->status = 0;
 		/* bogus test version */