kdrive: move bell ringing into an OS function

Move the bell into an OS function, and use that if it's declared; else,
fall back to using the driver's function.
Remove the Linux keyboard bell function; just move it into the OS layer.
Use named initialisers when converting the old structures, and eliminate
unused functions.

hw/kdrive/linux/linux.c

@@ -373,26 +373,6 @@ LinuxEnable (void)
     enabled = TRUE;
 }
 
-static Bool
-LinuxSpecialKey (KeySym sym)
-{
-    struct vt_stat  vts;
-    int		    con;
-    
-    if (XK_F1 <= sym && sym <= XK_F12)
-    {
-	con = sym - XK_F1 + 1;
-	memset (&vts, '\0', sizeof (vts));	/* valgrind */
-	ioctl (LinuxConsoleFd, VT_GETSTATE, &vts);
-	if (con != vts.v_active && (vts.v_state & (1 << con)))
-	{
-	    ioctl (LinuxConsoleFd, VT_ACTIVATE, con);
-	    return TRUE;
-	}
-    }
-    return FALSE;
-}
-
 static void
 LinuxDisable (void)
 {
@@ -481,13 +461,20 @@ KdOsAddInputDrivers ()
     KdAddKeyboardDriver(&LinuxKeyboardDriver);
 }
 
+static void
+LinuxBell(int volume, int pitch, int duration)
+{
+    if (volume && pitch)
+        ioctl(LinuxConsoleFd, KDMKTONE, ((1193190 / pitch) & 0xffff) |
+              (((unsigned long)duration * volume / 50) << 16));
+}
+
 KdOsFuncs   LinuxFuncs = {
-    LinuxInit,
-    LinuxEnable,
-    LinuxSpecialKey,
-    LinuxDisable,
-    LinuxFini,
-    0
+    .Init = LinuxInit,
+    .Enable = LinuxEnable,
+    .Disable = LinuxDisable,
+    .Fini = LinuxFini,
+    .Bell = LinuxBell,
 };
 
 void