`edit.c` needs optimizer turned off for all inline asm

[bobbimanners]

In edit.c there is a bunch of inline asm. the cc65 optimizer needs to be turned off (on a per function basis) using:

#pragma optimize (push,off)
...
#pragma optimize (pop)

Doing this naively results in the code overflowing the LC segment, so some refactoring is required.

If I don't fix this, most likely the code will break with newer cc65 releases.

[bobbimanners]

It seems to work okay for now, but this really should be addressed to avoid problems in future.