drm/nouveau/pmu: don't print reply values if exec is false

Currently the uninitialized values in the array reply are printed out
when exec is false and nvkm_pmu_send has not updated the array. Avoid
confusion by only dumping out these values if they have been actually
updated.

Detected by CoverityScan, CID#1271291 ("Uninitialized scaler variable")
Fixes: ebb58dc2 ("drm/nouveau/pmu: rename from pwr (no binary change)")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/subdev/pmu/memx.c

@@ -88,10 +88,10 @@ nvkm_memx_fini(struct nvkm_memx **pmemx, bool exec)
 	if (exec) {
 		nvkm_pmu_send(pmu, reply, PROC_MEMX, MEMX_MSG_EXEC,
 			      memx->base, finish);
+		nvkm_debug(subdev, "Exec took %uns, PMU_IN %08x\n",
+			   reply[0], reply[1]);
 	}
 
-	nvkm_debug(subdev, "Exec took %uns, PMU_IN %08x\n",
-		   reply[0], reply[1]);
 	kfree(memx);
 	return 0;
 }