cpu/stm32/periph: add low-level SDMMC peripheral driver

[gschorcht]

Contribution description

This PR implements the low-level SDIO/SDMMC peripheral driver for STM32 according to the definition in #19539. STM32 F2, F4 and F7 are supported. The DMA peripheral driver had to be extended for SDIO/SDMMC.

The PR also enables the SD Card Slot for the stm32f746g-disco and stm32l496g-disco.

Testing procedure

BOARD=stm32f746g-disco make -C tests/drivers/sdmmc

BOARD=stm32f746g-disco make -C tests/sys/vfs_default

Issues/PRs references

Depends on PR #19539
Depends on PR #19899
Depends on PR #20104

[gschorcht]

🤔 due to the last change the compilation fails now for applications that don't use periph_sdmmc for boards that have a sdmmc_config 😟 I'm wondering whether it is better also to embed these sdmmc_configs in preprocessor conditional using MODULE_PERIPH_SDMMC or to check for the existence of SDMMC_POWER_CTRL to embed the definition of the sdmmc_config_t in preprocessor conditionals to avoid compilation problems for MCUs that don't have a SDMMC peripheral.

[gschorcht]

@benpicco The alternative to af142f6 would be to embed the declaration static const sdmmc_conf_t sdmmc_config[] in the board definition in a preprocessor condition using the MODULE_PERIPH_SDMMC definition.

[benpicco]

af142f6 looks fine, let's squash and see what CI thinks of it

[gschorcht]

@benpicco I had to add HAS_PERIPH_SDMMC also to the Kconfig of the stm32f7508-dk board (335f4f8) because it is using the stm32f746g-disco board configuration but has its own Kconfig file 🙈 I didn't realize that before. Let's see whether it works now.

[benpicco]

I think you might as well remove the Kconfig altogether

[gschorcht]

I think you might as well remove the Kconfig altogether

@benpicco I just forgot also to add select HAVE_MTD_SDMMC_DEFAULT (a215d0d). It should work now.

[benpicco]

Please squash!

[gschorcht]

Thanks 😄