upgrade github.com/klauspost/compress to v1.11.6

This version has a fix that makes decoder.Reset(nil) release resources:
klauspost/compress@fa5ea64

decoderpool.go

@@ -47,10 +47,10 @@ type DecoderWrapper struct {
 // be reused), but instead resets it and places this *DecoderWrapper back in
 // the pool.
 func (w *DecoderWrapper) Close() {
-	// FIXME: https://github.com/klauspost/compress/issues/296
-	w.Decoder.Reset(nil)
-
-	w.pool.Put(w)
+	err := w.Decoder.Reset(nil)
+	if err != nil {
+		w.pool.Put(w)
+	}
 }
 
 // IOReadCloser returns an io.ReadCloser that will return this *DecoderWrapper

go.mod

@@ -2,4 +2,4 @@ module github.com/mostynb/zstdpool-syncpool
 
 go 1.15
 
-require github.com/klauspost/compress v1.11.4
+require github.com/klauspost/compress v1.11.6

go.sum

@@ -1,2 +1,2 @@
-github.com/klauspost/compress v1.11.4 h1:kz40R/YWls3iqT9zX9AHN3WoVsrAWVyui5sxuLqiXqU=
-github.com/klauspost/compress v1.11.4/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
+github.com/klauspost/compress v1.11.6 h1:EgWPCW6O3n1D5n99Zq3xXBt9uCwRGvpwGOusOLNBRSQ=
+github.com/klauspost/compress v1.11.6/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=