drm/amdgpu: check SMU NULL ptr on gfx hw init

Check SMU NULL ptr before load smu fw.
Signed-off-by: Likun Gao <Likun.Gao@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c

@@ -6540,6 +6540,7 @@ static int gfx_v10_0_hw_init(void *handle)
 		 * loaded firstly, so in direct type, it has to load smc ucode
 		 * here before rlc.
 		 */
+		if (adev->smu.ppt_funcs != NULL) {
 			r = smu_load_microcode(&adev->smu);
 			if (r)
 				return r;
@@ -6550,6 +6551,7 @@ static int gfx_v10_0_hw_init(void *handle)
 				return r;
 			}
 		}
+	}
 
 	/* if GRBM CAM not remapped, set up the remapping */
 	if (!gfx_v10_0_check_grbm_cam_remapping(adev))