Status output !TX/RX on the GDO2 CC1101 pin

[quen0n]

What's new

The essence is to display the transmission/reception status in the form of a logical level on the GDO2 pin of the CC1101 chip. This allows external devices to understand the current operating status of the radio chip
At rest, the GDO2 pin is in the floating-state. In receive/transmit mode, GDO2 switches to push-pull mode. When receiving, a logical 1 appears, when transmitting, a logical 0 appears. When the chip goes into rest mode, the GDO2 pin also returns to the floating-state
This can be used to control external signal amplifiers or to indicate the current state of the radio chip

Demo: https://disk.yandex.ru/d/kEsjUYyuDQM_gA

Verification

1. Go to SubGHz -> Read. А high logic level of 3.3 V (or other chip supply voltage) should appear at the GDO2 output
2. Just go to the SubGHz menu. The voltage on the GDO2 pin becomes unstable and can take on different values
3. Go to SubGHz -> Saved and send any saved signal. A logical zero (or 0 volt) will appear at the GDO2 output

Checklist (For Reviewer)

• PR has description of feature/bug
• Description contains actions to verify feature/bugfix
• I've built this code, uploaded it to the device and verified feature/bugfix