drm/amdgpu: initialize IP offset for navy_flounder

since navy_flounder has the same ip offset with sienna_cichlid,
follow sienna_cichlid setting for the moment.
Signed-off-by: Jiansong Chen <Jiansong.Chen@amd.com>
Reviewed-by: Tao Zhou <Tao.Zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -424,6 +424,7 @@ static int nv_reg_base_init(struct amdgpu_device *adev)
 		navi12_reg_base_init(adev);
 		break;
 	case CHIP_SIENNA_CICHLID:
+	case CHIP_NAVY_FLOUNDER:
 		sienna_cichlid_reg_base_init(adev);
 		break;
 	default: