[stm32wb_rng, rng] Implement RNG device type. Implement RNG driver ad test for stm32wb

[AlexLanzano]

No description provided.

[Copilot]

Pull request overview

Adds a new RNG abstraction to wolfHAL and provides an STM32WB (stm32wb55xx) TRNG implementation, wiring it into the STM32WB platform config and test suite.

Changes:

• Introduce generic RNG device/driver API (wolfHAL/rng/rng.h, src/rng/rng.c).
• Add STM32WB RNG driver + board/platform wiring (device + clock descriptors, RCC HSI48 helper).
• Add STM32WB hardware tests and hook them into the STM32WB test runner/build.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
wolfHAL/wolfHAL.h	Exposes RNG module via umbrella include.
wolfHAL/rng/rng.h	Defines generic RNG device struct + driver vtable + dispatch API.
wolfHAL/rng/stm32wb_rng.h	Declares STM32WB RNG driver config/API (and currently declares an RCC helper).
src/rng/rng.c	Implements generic RNG dispatch functions.
src/rng/stm32wb_rng.c	Implements STM32WB RNG init/deinit/generate and driver vtable.
wolfHAL/platform/st/stm32wb55xx.h	Adds STM32WB55 RNG device and its peripheral clock descriptor macros.
src/clock/stm32wb_rcc.c	Adds helper to enable/disable HSI48 oscillator needed by RNG.
examples/stm32wb/stm32wb55xx_nucleo.h	Exposes g_whalRng board instance.
examples/stm32wb/stm32wb55xx_nucleo.c	Instantiates g_whalRng with RCC clock gating config.
tests/stm32wb/test_rng.c	Adds STM32WB RNG hardware tests.
tests/stm32wb/test_main.c	Registers RNG tests in STM32WB test runner.
tests/stm32wb/Makefile	Adds test_rng.c to STM32WB test build.

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[Copilot]

Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated 4 comments.

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[Copilot]

SECS/CECS indicate hardware/clock/seed errors, not invalid arguments. Returning WHAL_EINVAL here is misleading; use WHAL_ENOTREADY (or introduce a more specific RNG error) so callers can distinguish argument validation from hardware failure.

Suggested change

	err = WHAL_EINVAL;
	goto exit;
	}
	whal_Reg_Get(reg->base, SRNG_SR_REG, SRNG_SR_CECS, &status);
	if (status) {
	err = WHAL_EINVAL;
	err = WHAL_ENOTREADY;
	goto exit;
	}
	whal_Reg_Get(reg->base, SRNG_SR_REG, SRNG_SR_CECS, &status);
	if (status) {
	err = WHAL_ENOTREADY;