move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/telegram/auth/qrlogin/options.go

@@ -0,0 +1,20 @@
+package qrlogin
+
+import (
+	"context"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/clock"
+)
+
+// Options of QR.
+type Options struct {
+	Migrate func(ctx context.Context, dcID int) error
+	Clock   clock.Clock
+}
+
+func (o *Options) setDefaults() {
+	// It's okay to use zero value Migrate.
+	if o.Clock == nil {
+		o.Clock = clock.System
+	}
+}