soc: silabs: Compilation fails if serial driver is disabled

[asmellby]

Describe the bug

If the serial driver is disabled, compilation fails.
This seems to be caused by several drivers, including gpio, implicitly depending on Clock Control but not selecting it. A workaround is to explicitly select CONFIG_CLOCK_CONTROL=y in the application.

Regression

• This is a regression.

Steps to reproduce

1. west build -p -b xg24_dk2601b samples/basic/blinky -DCONFIG_SERIAL=n

Relevant log output

zephyr/zephyr-sdk-0.17.4/arm-zephyr-eabi/bin/../lib/gcc/arm-zephyr-eabi/12.2.0/../../../../arm-zephyr-eabi/bin/ld.bfd: zephyr/drivers/gpio/libdrivers__gpio.a(gpio_silabs.c.obj):(.rodata.gpio_silabs_common_config_0+0x4): undefined reference to `__device_dts_ord_6'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.

Impact

Annoyance – Minor irritation; no significant impact on usability or functionality.

Environment

• OS: macOS
• Toolchain: Zephyr SDK
• Commit: 61a8648c2cc6bbec9af368a96ecae87d6798e7fe

Additional Context

No response