The high-performance snappy decoder does not support backpressure

[joosthooz]

This is a major issue especially when using multiple instances. We should consider removing the possibility of using this design altogether.
It has some more issues, such as needing to clear valid bits in BRAM after reset and each parquet page (it needs 512 cycles for that), and using much more BRAMs than conceptually needed (it uses a duplicate of the entire 64k data buffer instead of reconstructing data from a sliding window)