printk() indexing

I've even proposed that as good practice somewhere before. Just in case people need more selling on the idea:

The source code naturally contains LC_MESSAGES=C strings; those don't need to be written for anyone but the author and can shamelessly be optimised for high jargon density and minimum mental context switching. It gives a motive to write a human translation later, and even if that's just en_US with few changes you've now made a map of the terrain for anyone else to work with. There's a long tail of other benefits besides (such as, the one I started the thread with).