drm/amdgpu: fix context memory leak

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
index c23bfd8..859a484 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
@@ -130,6 +130,7 @@
 			DRM_ERROR("ctx %p is still alive\n", ctx);
 	}
 
+	idr_destroy(&mgr->ctx_handles);
 	mutex_destroy(&mgr->lock);
 }