drm/amdgpu/discovery: enable nbio support for NBIO v7.7.1

this patch is to enable nbio support for NBIO v7.7.1.

Signed-off-by: Yifan Zhang <[e-mail]>
Reviewed-by: Aaron Liu <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 		adev->nbio.hdp_flush_reg = &nbio_v4_3_hdp_flush_reg;
 		break;
 	case IP_VERSION(7, 7, 0):
+	case IP_VERSION(7, 7, 1):
 		adev->nbio.funcs = &nbio_v7_7_funcs;
 		adev->nbio.hdp_flush_reg = &nbio_v7_7_hdp_flush_reg;
 		break;