handle properly older sets power status

- while digging #90 and with the awesome help from @tjm7844 who provided
  live access to an affected set it was found that on some older sets
  the TV was returning X_ScreenState with a state ('none') when online
  not yet accounted by the plugin. this is now fixed and those TVs are
  now propperly recognized as ON when they actually are on.

Signed-off-by: António Meireles <antonio.meireles@reformi.st>

src/viera.ts

@@ -177,8 +177,10 @@ class VieraTV implements VieraTV {
           if (properties.X_ScreenState) {
             resolve(properties.X_ScreenState === 'on')
           } else if (Array.isArray(properties)) {
-            const match = properties.find((prop) => ['on', 'off'].includes(prop.X_ScreenState))
-            match ? resolve(match.X_ScreenState === 'on') : resolve(false)
+            const match = properties.find((prop) =>
+              ['on', 'off', 'none'].includes(prop.X_ScreenState)
+            )
+            match ? resolve(match.X_ScreenState !== 'off') : resolve(false)
           } else resolve(false)
         })
         .on('error', () => resolve(false))