Replace individual CMS vtx menus with a single entry that redirects to the correct protocol menu

Instead of having individual menus for RTC6705, SmartAudio, and Tramp, Now there is a single VTX menu that detects the type of active device and redirects to the appropriate protocol menu.

Reduces confusion and chances of erroneously using the wrong VTX menu.

Fixes a problem where the Tramp menu could be used to change band/channel/power even though the VTX was a SmartAudio device.

If the VTX is not configured or not communicating, a more informative message will be presented rather than a partially populated protocol menu. For example:
```
  VTX NOT RESPONDING
  OR NOT CONFIGURED

> BACK
```

Extends the CMS menu capabilities by adding an optional `redirectCheck` function that can conditionally return a menu that should be redirected to instead of the current menu. This redirect happens before any processing happens for the original menu. Adds flexibility to make the CMS menus have a more dynamic aspect.

src/main/cms/cms.c

@@ -654,6 +654,13 @@ long cmsMenuChange(displayPort_t *pDisplay, const void *ptr)
             return 0;
         }
 
+        if (pMenu->checkRedirect) {
+            const CMS_Menu *pRedirectMenu = (const CMS_Menu *)pMenu->checkRedirect();
+            if (pRedirectMenu) {
+                return cmsMenuChange(pDisplay, pRedirectMenu);
+            }
+        }
+
         menuStack[menuStackIdx++] = currentCtx;
 
         currentCtx.menu = pMenu;