bindings: Update copyrights

src/xrt/auxiliary/bindings/CMakeLists.txt

-# Copyright 2019-2020, Collabora, Ltd.
+# Copyright 2019-2021, Collabora, Ltd.
 # SPDX-License-Identifier: BSL-1.0
 
 ###

src/xrt/auxiliary/bindings/bindings.json.license

-Copyright 2020, Collabora, Ltd.
+Copyright 2020-2021, Collabora, Ltd.
 
-SPDX-License-Identifier: BSL-1.0
\ No newline at end of file
+SPDX-License-Identifier: BSL-1.0

src/xrt/auxiliary/bindings/bindings.py

 #!/usr/bin/env python3
-# Copyright 2020, Collabora, Ltd.
+# Copyright 2020-2021, Collabora, Ltd.
 # SPDX-License-Identifier: BSL-1.0
 """Generate code from a JSON file describing interaction profiles and
 bindings."""

src/xrt/auxiliary/bindings/meson.build

-# Copyright 2019-2020, Collabora, Ltd.
+# Copyright 2019-2021, Collabora, Ltd.
 # SPDX-License-Identifier: BSL-1.0
 
 ###