Bump gocui

... and switch back from stefanhaller's tcell fork to the official tcell. This
basically reverts 7ccb871a45.

vendor/github.com/gdamore/tcell/v2/nonblock_unix.go

@@ -0,0 +1,41 @@
+// Copyright 2021 The TCell Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use file except in compliance with the License.
+// You may obtain a copy of the license at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build linux || aix || zos || solaris
+// +build linux aix zos solaris
+
+package tcell
+
+import (
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+// tcSetBufParams is used by the tty driver on UNIX systems to configure the
+// buffering parameters (minimum character count and minimum wait time in msec.)
+// This also waits for output to drain first.
+func tcSetBufParams(fd int, vMin uint8, vTime uint8) error {
+	_ = syscall.SetNonblock(fd, true)
+	tio, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return err
+	}
+	tio.Cc[unix.VMIN] = vMin
+	tio.Cc[unix.VTIME] = vTime
+	if err = unix.IoctlSetTermios(fd, unix.TCSETSW, tio); err != nil {
+		return err
+	}
+	return nil
+}