drivers: i2c: wch: Add support i2c target

[bozheng1988]

Add support i2c target for wch, tested on WCH-CH32V203EVT board

[github-actions]

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[Copilot]

Pull Request Overview

This PR adds I2C target (slave) mode support to the WCH I2C driver, enabling devices to act as I2C slaves in addition to the existing master functionality. The implementation includes interrupt handling for slave events and proper state management to handle both master and slave operations.

• Adds I2C target mode configuration and state management
• Implements slave event and error interrupt handling
• Provides target registration and unregistration functions

Comments suppressed due to low confidence (1)

drivers/i2c/i2c_wch.c:589

• The log message uses 'slave' terminology while the rest of the code uses 'target' terminology. Should be 'i2c: target unregistered' for consistency.

	LOG_DBG("i2c: slave unregistered");

[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