SFV file can be stored twice in the SRR

When creating an SRR with srr.py, the .sfv must not be provided as file to store since this is done automatically. Providing the .sfv anyway results in the file being stored twice. Tested on a music and video release.

rescene.php will show the following warning: [0] => Duplicate file detected!

Low priority since srr.py shouldn't be used anymore to create .srr files by hand. The Auto script should be able to handle it all.