trezor: use `init_device` instead of `ping` to check connection (fixes #6457) (#6471)

electrum/plugins/trezor/clientbase.py

@@ -112,8 +112,7 @@ class TrezorClientBase(HardwareClientBase, Logger):
             return True
 
         try:
-            res = self.client.ping("electrum pinging device")
+            self.client.init_device()
-            assert res == "electrum pinging device"
         except BaseException:
             return False
         return True