fix : ZSTD_compress_generic(,,,ZSTD_e_end) automatically sets pledgedSrcSize

fix : ZSTD_compress_generic(,,,ZSTD_e_end) automatically sets pledgedSrcSize

as per documentation, on ZSTD_setPledgedSrcSize() :
> If all data is provided and consumed in a single round,
> this value (pledgedSrcSize) is overriden by srcSize instead.

This wasn't applied before compression level is transformed into compression parameters.
As a consequence, small input missed compression parameters adaptation.

It seems to work fine now : compression was compared with ZSTD_compress_advanced(),
results were the same.