Allow 2+ connections to BLE devices

[xcelente]

AFAIK there is a limitation in the meshtastic firmware that does not exist at the hw level; connecting to 2 or more BLE devices at the same time. There are at least 2 legitimate use cases:

1. Connecting both a phone and a computer at the same time.

2. redundancy for emergency situations i.e. one device connection fails, the other device may still catch the packets