drm/nv50-/disp: audit and version PIOR_PWR method

The full object interfaces are about to be exposed to userspace, so we
need to check for any security-related issues and version the structs
to make it easier to handle any changes we may need in the future.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/core/engine/disp/nv50.c b/drivers/gpu/drm/nouveau/core/engine/disp/nv50.c
index ed55cc2..d83d3ef 100644
--- a/drivers/gpu/drm/nouveau/core/engine/disp/nv50.c
+++ b/drivers/gpu/drm/nouveau/core/engine/disp/nv50.c
@@ -952,6 +952,10 @@
 			return ret;
 	}
 		break;
+	case NV50_DISP_MTHD_V1_PIOR_PWR:
+		if (!priv->pior.power)
+			return -ENODEV;
+		return priv->pior.power(object, priv, data, size, head, outp);
 	default:
 		break;
 	}
@@ -1080,9 +1084,6 @@
 static struct nouveau_omthds
 nv50_disp_base_omthds[] = {
 	{ HEAD_MTHD(NV50_DISP_SCANOUTPOS)     , nv50_disp_base_scanoutpos },
-	{ PIOR_MTHD(NV50_DISP_PIOR_PWR)       , nv50_pior_mthd },
-	{ PIOR_MTHD(NV50_DISP_PIOR_TMDS_PWR)  , nv50_pior_mthd },
-	{ PIOR_MTHD(NV50_DISP_PIOR_DP_PWR)    , nv50_pior_mthd },
 	{},
 };