cpu is greater than 100% when close() is called

[yellzhi]

1. When the resident process called close(), cpu utilization exceeds 100%

2.we found a possible code:

` ledger_hid.go

func (ledger *LedgerDeviceHID) readThread() {
defer close(ledger.readChannel)
for {
	buffer := make([]byte, PacketSize)
	readBytes, err := ledger.device.Read(buffer)

	// Check for HID Read Error (May occur even during normal runtime)
	if err != nil {
		continue
	}

	// Discard all zero packets from Ledger Nano X on macOS
	allZeros := true
	for i := 0; i < len(buffer); i++ {
		if buffer[i] != 0 {
			allZeros = false
			break
		}
	}

	// Discard all zero packet
	if allZeros {
		// HID Returned Empty Packet - Retry Read
		continue
	}

	select {
	case ledger.readChannel <- buffer[:readBytes]:
		// Send data to UnwrapResponseAPDU
	default:
		// Possible source of bugs
		// Drop a buffer if ledger.readChannel is busy
	}
}

}

`