gzhttp: remove redundant err check in zstdReader

Author: ryanfowler

gzhttp/transport.go

@@ -208,14 +208,12 @@ func (zr *zstdReader) Read(p []byte) (n int, err error) {
 		return 0, zr.zerr
 	}
 	if zr.zr == nil {
-		if zr.zerr == nil {
-			reader, ok := zstdReaderPool.Get().(*zstd.Decoder)
-			if ok {
-				zr.zerr = reader.Reset(zr.body)
-				zr.zr = reader
-			} else {
-				zr.zr, zr.zerr = zstd.NewReader(zr.body, zstd.WithDecoderLowmem(true), zstd.WithDecoderMaxWindow(32<<20), zstd.WithDecoderConcurrency(1))
-			}
+		reader, ok := zstdReaderPool.Get().(*zstd.Decoder)
+		if ok {
+			zr.zerr = reader.Reset(zr.body)
+			zr.zr = reader
+		} else {
+			zr.zr, zr.zerr = zstd.NewReader(zr.body, zstd.WithDecoderLowmem(true), zstd.WithDecoderMaxWindow(32<<20), zstd.WithDecoderConcurrency(1))
 		}
 		if zr.zerr != nil {
 			return 0, zr.zerr