[vtx] Add VTX driver with Tramp and SmartAudio support

msg/Vtx.msg

@@ -0,0 +1,32 @@
+uint64 timestamp # time since system start (microseconds)
+
+uint8 BAND_NAME_LENGTH = 12
+uint8 POWER_LABEL_LENGTH = 4
+
+uint8 PROTOCOL_NONE = 0              # No protocol is detected, usually an error
+uint8 PROTOCOL_SMART_AUDIO_V1 = 10
+uint8 PROTOCOL_SMART_AUDIO_V2 = 20
+uint8 PROTOCOL_SMART_AUDIO_V2_1 = 21
+uint8 PROTOCOL_TRAMP = 100
+uint8 protocol
+
+uint8 DEVICE_UNKNOWN = 0
+uint8 DEVICE_PEAK_THOR_T67 = 20
+uint8 DEVICE_RUSH_MAX_SOLO = 40
+uint8 device
+
+uint8 MODE_NORMAL = 0
+uint8 MODE_PIT = 1
+uint8 mode
+
+# Band and Channel are 0-indexed! But the user expects a 1-indexed display!
+int8 band        # Band number (0-23), negative values indicate frequency mode
+int8 channel     # Channel number (0-15), negative values indicate frequency mode
+uint16 frequency # Frequency in MHz, zero indicates unknown
+
+uint8 band_letter   # Band letter as ASCII
+uint8[12] band_name # Band name in ASCII without null termination
+
+# Also 0-indexed, but the user expects a 1-indexed display!
+int8 power_level     # Current power level (0-15), negative values indicate unknown
+uint8[4] power_label # Current power label in ASCII without null termination