drm/radeon: add new richland pci ids

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/radeon/ni.c b/drivers/gpu/drm/radeon/ni.c
index 7436b91..7969c0c 100644
--- a/drivers/gpu/drm/radeon/ni.c
+++ b/drivers/gpu/drm/radeon/ni.c
@@ -749,7 +749,8 @@
 		    (rdev->pdev->device == 0x990F) ||
 		    (rdev->pdev->device == 0x9910) ||
 		    (rdev->pdev->device == 0x9917) ||
-		    (rdev->pdev->device == 0x9999)) {
+		    (rdev->pdev->device == 0x9999) ||
+		    (rdev->pdev->device == 0x999C)) {
 			rdev->config.cayman.max_simds_per_se = 6;
 			rdev->config.cayman.max_backends_per_se = 2;
 		} else if ((rdev->pdev->device == 0x9903) ||
@@ -758,7 +759,8 @@
 			   (rdev->pdev->device == 0x990D) ||
 			   (rdev->pdev->device == 0x990E) ||
 			   (rdev->pdev->device == 0x9913) ||
-			   (rdev->pdev->device == 0x9918)) {
+			   (rdev->pdev->device == 0x9918) ||
+			   (rdev->pdev->device == 0x999D)) {
 			rdev->config.cayman.max_simds_per_se = 4;
 			rdev->config.cayman.max_backends_per_se = 2;
 		} else if ((rdev->pdev->device == 0x9919) ||