1475: Add YieldingAsync adapter r=Dirbaio a=rmja
This PR calls `yield_now()` for long blocking `NorFlash` read and erase operations.
The motivation for this change is to allow for other tasks on the same executor to get something done between these long running operations, for example a task that feeds a watchdog. This will allow the watchdog to have a timer relative to e.g. one sector erase, instead of all sector erase.
1478: stm32: Minor fixes in flash regions for F4 dual bank layout r=Dirbaio a=rmja
This PR has the following fixes:
* Ensure that `FlashRegion` instances can only be created within the embassy-stm32 crate.
* Remove `Drop` trait for `AltFlashLayout`, as it is hard to use, as one cannot take the individual regions out from the struct. Instead of going back to single bank mode on `Drop`, we instead transition to single bank mode when calling `Flash::into_regions()`.
* Add missing `otp_region` to the dual bank layout and implement `NorFlash` for the alternate regions.
1482: Add ConcatFlash utility r=Dirbaio a=rmja
This PR adds a `ConcatFlash` utility that can be used to concatenate two `NorFlash` flashes. This is especially useful when concatenating multiple flash regions with unequal erase size.
Co-authored-by: Rasmus Melchior Jacobsen <rmja@laesoe.org>