Fix SPI45 2MHz clock source

[jorgesg82]

Summary

• Route SPI4/SPI5 peripheral clocks from HSI instead of PCLK2 during SPI domain initialization.
• Explicitly keep HSI enabled at divide-by-1 in the system clock setup.

Why

The current code drives SPI4/SPI5 from PCLK2. With the board clock tree, that source is not an exact power-of-two multiple of 2 MHz, so the SPI prescaler calculation cannot land exactly on the requested BMS SPI rate.

HSI provides a 64 MHz source. With the existing 2 MHz max baud request, ST-LIB selects the /32 SPI prescaler, producing a deterministic 2 MHz SPI4 SCK.

Important

This is need for the HVBMS to work properly

Warning

This may affect other boards that use SPI4 with a different baudrate, if the requested one cannot be properly determined prescaling 64MHz

[github-actions]

ST-LIB Release Plan

• Current version: 6.1.2
• Pending changesets: 1
• Highest requested bump: patch
• Next version if merged now: 6.1.3

Pending changes

• patch Drive SPI4 and SPI5 from HSI for stable 2 MHz BMS transfers (.changesets/spi45-hsi-clock-source.md)

[Copilot]

Pull request overview

This PR aims to make SPI4/SPI5 clocking deterministic for a 2 MHz baud request (notably for HVBMS) by sourcing SPI45 from the 64 MHz HSI clock rather than the APB clock path, and by ensuring HSI remains enabled during system clock setup.

Changes:

• Enable/configure HSI in HALconfig::system_clock() so SPI45 can reliably use HSI.
• Switch SPI4 and SPI5 peripheral clock selection to RCC_SPI45CLKSOURCE_HSI during SPI domain initialization.
• Add a patch changeset documenting the SPI45 clock-source change.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
Src/HALAL/Models/HALconfig/Halconfig.cpp	Updates oscillator configuration to include HSI so it can be used as a peripheral clock source.
Inc/HALAL/Models/SPI/SPI2.hpp	Routes SPI4/SPI5 peripheral clocks to HSI when initializing SPI instances.
.changesets/spi45-hsi-clock-source.md	Adds release note entry describing the SPI45 clock-source change.

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