Removed PFS code from C128 WGET.

On the C128 the custom PFS code doesn't add functionality (as it does with IDE64 support on the C64) but is "only" smaller than the POSIX file i/o code in the C library. But the stdio code in the C library (used in WGET for screen i/o) relies on the POSIX file i/o code anyway so there no point in additionally adding the PFS code to the WGET program.