This replaces the repetitive GPL-2.0 license text in code and header files
with the SPDX tags. Generated hardware headers aren't changed, as any changes
there need to be done in the upstream rnndb repository.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Reviewed-by: NChristian Gmeiner <christian.gmeiner@gmail.com>