Provide an interface for fuzzing sequence producer plugins

tests/fuzz/stream_round_trip.c

@@ -22,6 +22,7 @@
 #include "fuzz_helpers.h"
 #include "zstd_helpers.h"
 #include "fuzz_data_producer.h"
+#include "fuzz_third_party_seq_prod.h"
 
 ZSTD_CCtx *cctx = NULL;
 static ZSTD_DCtx *dctx = NULL;
@@ -133,6 +134,7 @@ static size_t compress(uint8_t *dst, size_t capacity,
 
 int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
 {
+    FUZZ_SEQ_PROD_SETUP();
     size_t neededBufSize;
 
     /* Give a random portion of src data to the producer, to use for
@@ -191,5 +193,6 @@ int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
     ZSTD_freeCCtx(cctx); cctx = NULL;
     ZSTD_freeDCtx(dctx); dctx = NULL;
 #endif
+    FUZZ_SEQ_PROD_TEARDOWN();
     return 0;
 }