doc: Fix zstd documentation (#243)

* zstd: remove reference to non-existent function
* zstd: correct names constants in documentation

Co-authored-by: greatroar <@>

Author: greatroar

zstd/decoder.go

@@ -66,7 +66,7 @@ var (
 // A Decoder can be used in two modes:
 //
 // 1) As a stream, or
-// 2) For stateless decoding using DecodeAll or DecodeBuffer.
+// 2) For stateless decoding using DecodeAll.
 //
 // Only a single stream can be decoded concurrently, but the same decoder
 // can run multiple concurrent stateless decodes. It is even possible to

zstd/encoder_options.go

@@ -69,7 +69,7 @@ func WithEncoderConcurrency(n int) EOption {
 }
 
 // WithWindowSize will set the maximum allowed back-reference distance.
-// The value must be a power of two between WindowSizeMin and WindowSizeMax.
+// The value must be a power of two between MinWindowSize and MaxWindowSize.
 // A larger value will enable better compression but allocate more memory and,
 // for above-default values, take considerably longer.
 // The default value is determined by the compression level.