drm/amdgpu: add Stoney chip family

Stoney is based on Carrizo with some IP upgrades.
Signed-off-by: Samuel Li <samuel.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -57,6 +57,7 @@ static const char *amdgpu_asic_name[] = {
 	"TONGA",
 	"FIJI",
 	"CARRIZO",
+	"STONEY",
 	"LAST",
 };
 

drivers/gpu/drm/amd/include/amd_shared.h

@@ -47,6 +47,7 @@ enum amd_asic_type {
 	CHIP_TONGA,
 	CHIP_FIJI,
 	CHIP_CARRIZO,
+	CHIP_STONEY,
 	CHIP_LAST,
 };