Take mutexes for sake of consistency (Coverity)

bin/varnishtest/vtc_process.c

@@ -1067,7 +1067,9 @@ cmd_process(CMD_ARGS)
 		p = process_new(av[0]);
 	av++;
 
+	PTOK(pthread_mutex_lock(&p->mtx));
 	bsnap = p->stdout_bytes;
+	PTOK(pthread_mutex_unlock(&p->mtx));
 
 	for (; *av != NULL; av++) {
 		if (vtc_error)

vmod/vmod_debug_dyn.c

@@ -155,10 +155,14 @@ xyzzy_dyn__fini(struct xyzzy_debug_dyn **dynp)
 VCL_BACKEND v_matchproto_()
 xyzzy_dyn_backend(VRT_CTX, struct xyzzy_debug_dyn *dyn)
 {
+	VCL_BACKEND retval;
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
 	CHECK_OBJ_NOTNULL(dyn, VMOD_DEBUG_DYN_MAGIC);
-	AN(dyn->dir);
-	return (dyn->dir);
+	PTOK(pthread_mutex_lock(&dyn->mtx));
+	retval = dyn->dir;
+	PTOK(pthread_mutex_unlock(&dyn->mtx));
+	AN(retval);
+	return (retval);
 }
 
 VCL_VOID