Fix comment for I2C_CLK_LIMIT_XTAL definition

[kakmonk]

Updating the comment to signal its limitation to XTAL, not RTC, to avoid confusion.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sylvioalves]

Hi @kakmonk, I think all those defines (I2C_CLK_LIMI_xxx) are not being used at all and is probably leftovers from initial code. Perhaps you could update your PR to remove it all instead.

[sylvioalves]

Closing this due to #100630