It wasn't working, I'm not really sure why.
Since #2997 we rely on video common to mark efb copies 'written'
during recording, and for old dffs we just ignore the bad texture
while playing back in the texture cache.
We actually discovered a bug while combining the two functions with
FifoRecordAnalzyer's vertex array loading code. If per-vertex
postion or texture matrices were enabled and vertex arrays in use
then the wrong data would be used to calculate the minimum/maxmium
indices, which would result in either too much or too little vertex
data being included in the dff.
So this commit also increments the dff version number, so we can
identify old broken dffs later.
- remove unused variables
- reduce the scope where it makes sense
- correct limits (did you know that strcat()'s last parameter does not
include the \0 that is always added?)
- set some free()'d pointers to NULL
