fuzz: improves sigpcap target with PacketPoolInit

src/tests/fuzz/fuzz_sigpcap.c

@@ -79,7 +79,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
         tmm_modules[TMM_FLOWWORKER].ThreadInit(&tv, NULL, &fwd);
         StatsSetupPrivate(&tv);
 
-        PacketPoolInitEmpty();
+        PacketPoolInit();
         initialized = 1;
     }