- Removed conditional definitions for various RCC_ATOMIC macros across
multiple files, replacing them with a unified PERIPH_RCC_ATOMIC() macro.
- Updated instances where specific RCC_ATOMIC macros were used to ensure
consistent usage of PERIPH_RCC_ATOMIC().
- Deleted unused uart_share_hw_ctrl.h file as its functionality is now
integrated into the new structure.
Host and device (card, etc.) initialization is not thread-safe.
After initialization transactions are serialized and guarded by mutex.
Changed `SDMMC_HOST_DEFAULT()` default deinit function to `sdmmc_host_deinit_slot`
which has a slot number as argument.
