Need to use proper way to delete VMU savefiles

[Protofall]

BlueCrab said I shouldn't be using vmufs_ stuff and instead I should be using unlink() for deleting the savefiles.

If not unlink, maybe just remove() for both

[Protofall]

unlink() removes the file entry and marks the blocks as free.

BlueCrab: I believe that doing a stat on the /vmu/a1 (or whatever) directory should tell you the number of blocks.