I asked @tuukka.pasanen_ilmi.fi to put this one in review to facilitate discussion.

style(9) shows the SPDX tag coming after the copyright statement, not before as here. However, the example there does not have the additional text that this one does, so per style(9) should the SPDX tag go before the "This code is..." or before "Redistribution and ..."? Files that have two separate copyright blocks also make it somewhat unclear where it should go -- between the copyright statement and the license text in the first block?

It's very common in our tree to have the SPDX tag before the copyright statement and it seems there are many cases where that makes sense.