accel/qaic: Validate if BO is sliced before slicing

QAIC_ATTACH_SLICE_BO attaches slicing configuration to a BO. Validate if
given BO is already sliced. An already sliced BO cannot be sliced again.

Fixes: ff13be83 ("accel/qaic: Add datapath")
Signed-off-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@quicinc.com>
Reviewed-by: Carl Vanderlip <quic_carlv@quicinc.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230517193540.14323-3-quic_jhugo@quicinc.com

drivers/accel/qaic/qaic_data.c

@@ -1001,6 +1001,11 @@ int qaic_attach_slice_bo_ioctl(struct drm_device *dev, void *data, struct drm_fi
 
 	bo = to_qaic_bo(obj);
 
+	if (bo->sliced) {
+		ret = -EINVAL;
+		goto put_bo;
+	}
+
 	ret = qaic_prepare_bo(qdev, bo, &args->hdr);
 	if (ret)
 		goto put_bo;