Fix varnishtest barrier error messages

Spotted by @fgsch

bin/varnishtest/vtc_barrier.c

@@ -325,7 +325,7 @@ barrier_sock_sync(struct barrier *b, struct vtclog *vl)
 	AZ(close(sock));
 
 	if (sz < 0)
-		vtc_log(vl, 0, "Barrier(%s) connection failed: %s (errno=%d)",
+		vtc_log(vl, 0, "Barrier(%s) read failed: %s (errno=%d)",
 		    b->name, strerror(i), i);
 	if (sz > 0)
 		vtc_log(vl, 0, "Barrier(%s) unexpected data (%ldB)",

lib/libvmod_debug/vmod_debug.c

@@ -507,7 +507,7 @@ vmod_barrier_sync(VRT_CTX, VCL_STRING addr)
 		return (1);
 	if (sz < 0)
 		VSLb(ctx->vsl, SLT_Error,
-		    "Barrier connection failed: %s (errno=%d)", strerror(i), i);
+		    "Barrier read failed: %s (errno=%d)", strerror(i), i);
 	if (sz > 0)
 		VSLb(ctx->vsl, SLT_Error, "Barrier unexpected data (%ldB)", sz);
 	return (0);