Lines are still way too long in many cases, so this series takes
two further steps towards shrinking. While the 1st patch is
hopefully going to be uncontroversial, the 2nd one might be, and
has a respective RFC remark for this very reason. Due to their
size I'm attaching both patches here, and I'll include only
abridged variants (with only some opcode table hunks retained,
just to demonstrate the transformation done, but of course with
all changes to other [non-generated] files retained).

1: change representation of extension opcode
2: omit Cpu prefixes in opcode table

Jan