added support for EP0099

[cadusk]

EP0099 is a stackable 4-channel relay hat that communicates with
platforms via i2c interface.

Manufacturer: 52pi
Wiki page: https://wiki.52pi.com/index.php/DockerPi_4_Channel_Relay_SKU:_EP-0099

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[codecov-io]

Codecov Report

Merging #5 (ccc1c29) into main (296894b) will increase coverage by 0.1%.
The diff coverage is 82.9%.

@@           Coverage Diff           @@
##            main      #5     +/-   ##
=======================================
+ Coverage   63.2%   63.3%   +0.1%     
=======================================
  Files         46      47      +1     
  Lines       4034    4069     +35     
=======================================
+ Hits        2549    2574     +25     
- Misses      1357    1364      +7     
- Partials     128     131      +3     

Impacted Files	Coverage Δ
ep0099/ep0099.go	82.9% <82.9%> (ø)
lepton/lepton.go	85.7% <0.0%> (-1.4%)	⬇️
as7262/as7262.go	98.0% <0.0%> (-1.0%)	⬇️

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[maruel]

I'm fine with committing as is or with optional changes, as you prefer.

[maruel]

It's the default so you can skip the whole line.

[cadusk]

this makes sense. will remove it.

[cadusk]

I like this approach, I just don't see how to figure out which channel we're referring to in method Out since we're passing the index to the array, not to dev.

type (r *Relay) Out(l gpio.Level) error {
	_, err := d.i2c.Write([]byte{channel, byte(StateOn)})
	r.state = StateOn
	return err
}

I've been learning a lot with this PR, maybe there's a way to figure out what channel would be without looping through Relays and comparing d to items in the array.

Maybe this solution needs some more thinking.
I am happy with the results so far and am ok with merging it like this.

[maruel]

One last point: do you mind following the instruction at #5 (comment)?

[maruel]

gohci

[maruel]

Thanks!