drm/amd/display: free bo used for dmub bounding box

fix a memleak introduced by not removing the buffer object for use with
early dmub bounding box value storage

Fixes: 234e9455 ("drm/amd/display: Enable copying of bounding box data from VBIOS DMUB")
Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -1740,7 +1740,7 @@ static struct dml2_soc_bb *dm_dmub_get_vbios_bounding_box(struct amdgpu_device *
 		/* Send the chunk */
 		ret = dm_dmub_send_vbios_gpint_command(adev, send_addrs[i], chunk, 30000);
 		if (ret != DMUB_STATUS_OK)
-			/* No need to free bb here since it shall be done unconditionally <elsewhere> */
+			/* No need to free bb here since it shall be done in dm_sw_fini() */
 			return NULL;
 	}
 
@@ -2465,8 +2465,17 @@ static int dm_sw_init(void *handle)
 static int dm_sw_fini(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+	struct dal_allocation *da;
+
+	list_for_each_entry(da, &adev->dm.da_list, list) {
+		if (adev->dm.bb_from_dmub == (void *) da->cpu_ptr) {
+			amdgpu_bo_free_kernel(&da->bo, &da->gpu_addr, &da->cpu_ptr);
+			list_del(&da->list);
+			kfree(da);
+			break;
+		}
+	}
 
-	kfree(adev->dm.bb_from_dmub);
 	adev->dm.bb_from_dmub = NULL;
 
 	kfree(adev->dm.dmub_fb_info);