Conditionally load EDID on device with TC358743 capture chip

[jdeanwallace]

Resolves #1726

This PR only starts the load-tc358743-edid.service when a TC358743 capture chip is installed. This change avoids reporting the service as "failed" when a TC358743 capture chip is not installed on the device.

Caveat: The load-tc358743-edid.service process is still marked as (code=exited, status=1/FAILURE), but it's active state is no longer failed (Result: exit-code). Instead, its active state is inactive (dead) (Result: exec-condition).

Example output of service being skipped:

Jan 28 18:41:02 raspberrypi systemd[1]: Starting Load EDID for TC358743 HDMI capture chip....
Jan 28 18:41:02 raspberrypi systemd[1]: load-tc358743-edid.service: Control process exited, code=exited, status=1/FAILURE
Jan 28 18:41:02 raspberrypi systemd[1]: load-tc358743-edid.service: Skipped due to 'exec-condition'.
Jan 28 18:41:02 raspberrypi systemd[1]: Condition check resulted in Load EDID for TC358743 HDMI capture chip. being skipped.

[jdeanwallace]

Automated comment from CodeApprove ➜

⏳ @db39 please review this Pull Request

[db39]

Automated comment from CodeApprove ➜

✔️ Approved

LGTM, thanks! Having the service inactive (instead of failed) by default definitely helps!

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👀 @jdeanwallace it's your turn please take a look