cochran: do the full de-scramble for one case

So this descrambles all the dives in *one* of my cochran test files.  I
still don't know what the dive data *means*, but it's not a random
jumble of bytes any more: there are very clear patterns.

However, the magic offsets that work for that particular CAN file are
not generic, because they don't work for another.  So there is some
magic dynamic decoding that I don't know about.  There is probably more
decode information in the initial decode block, over and beyond just the
scrambling bytes.

(The scrambling array is 234 bytes starting at 0x40001, but the first
actual *dive* data starts at 0x45e03, so there's tons of unknown stuff
in the file even outside the dives themselves)

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>