[moserial] Add 3MBaud rate.

[Michael J. Chudobiak <mjc src gnome org>]

commit ad233e2e64b5c2501f55325d583d4737413a3b6d
Author: Mictronics <github mictronics de>
Date:   Mon Apr 27 16:32:12 2020 +0200

    Add 3MBaud rate.

 src/SerialConnection.vala | 3 +++
 src/Settings.vala         | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/src/SerialConnection.vala b/src/SerialConnection.vala
index ff20bc0..038d718 100644
--- a/src/SerialConnection.vala
+++ b/src/SerialConnection.vala
@@ -199,6 +199,9 @@ public class moserial.SerialConnection : GLib.Object {
             case 2000000:
                 baudRate = Linux.Termios.B2000000;
                 break;
+            case 3000000:
+                baudRate = Linux.Termios.B3000000;
+                break;
         }
 
         Posix.cfsetospeed (ref newtio, baudRate);
diff --git a/src/Settings.vala b/src/Settings.vala
index a923ac8..7e99610 100644
--- a/src/Settings.vala
+++ b/src/Settings.vala
@@ -40,7 +40,8 @@ public class Settings : GLib.Object {
                                             "4800", "9600", "19200",
                                             "38400", "57600", "115200",
                                             "230400", "460800", "576000",
-                                            "921600", "1000000", "2000000" };
+                                            "921600", "1000000", "2000000",
+                                            "300000" };
 
     public static string DEFAULT_DEVICEFILE = "/dev/ttyS0";
     public static int DEFAULT_BAUDRATE = 1200;