go.mod: require go-delve/liner instead of peterh/liner (#2905)

Use of `replace` in go.mod breaks delve installation using
`go install`. (see https://github.com/golang/go/issues/40276)
Workaround this limitation by explicitly require the fork
github.com/go-delve/liner.

go-delve/liner@v1.2.2-1 already has go.mod module name fixed
to be github.com/go-delve/liner.

Fixes go-delve/delve#2904

vendor/github.com/go-delve/liner/input_darwin.go

@@ -0,0 +1,44 @@
+//go:build darwin
+// +build darwin
+
+package liner
+
+import "syscall"
+
+const (
+	getTermios = syscall.TIOCGETA
+	setTermios = syscall.TIOCSETA
+)
+
+const (
+	// Input flags
+	inpck  = 0x010
+	istrip = 0x020
+	icrnl  = 0x100
+	ixon   = 0x200
+
+	// Output flags
+	opost = 0x1
+
+	// Control flags
+	cs8 = 0x300
+
+	// Local flags
+	isig   = 0x080
+	icanon = 0x100
+	iexten = 0x400
+)
+
+type termios struct {
+	Iflag  uintptr
+	Oflag  uintptr
+	Cflag  uintptr
+	Lflag  uintptr
+	Cc     [20]byte
+	Ispeed uintptr
+	Ospeed uintptr
+}
+
+// Terminal.app needs a column for the cursor when the input line is at the
+// bottom of the window.
+const cursorColumn = true