WriteWithoutResponse in Bluez picks different write types

[tazjin]

Hey, thanks for this library!

Currently WriteWithoutResponse for Bluez doesn't specify a type when writing:

bluetooth/gattc_linux.go

Lines 224 to 230 in 5c61529

	func (c DeviceCharacteristic) WriteWithoutResponse(p []byte) (n int, err error) {
	err = c.characteristic.Call("org.bluez.GattCharacteristic1.WriteValue", 0, p, map[string]dbus.Variant(nil)).Err
	if err != nil {
	return 0, err
	}
	return len(p), nil
	}

In Bluez, the type of write is set at this call: https://github.com/bluez/bluez/blob/c6dcf6b714501768ab7ea293e75d945be0eec188/doc/org.bluez.GattCharacteristic.rst#L97-L111

If it is unset, Bluez seems to chose one based on the properties of the characteristic: https://github.com/bluez/bluez/blob/c6dcf6b714501768ab7ea293e75d945be0eec188/src/gatt-client.c#L1066-L1113

I might be missing something, but it seems like the function is currently more like a WriteAuto which picks the first fitting type.

As for how to resolve it, I'm not sure. This logic is actually quite useful, but it should probably live under a different name, and explicit command/request functions could be added/fixed as needed.