The external SPI flash is implemented as a 4MB on the local filesystem.
This allows the FS (littleFS) and settings to work properly.
Remove the simulated `FS.h` and `FS.cpp`, because we can now use
the files from InfiniTime directly as the heavy lifting is done in the simulated
`SpiNorFlash.h` and cpp files.
`SpiNorFlash.h` provides read and write functions with `uint8_t` buffer, but
`fs::fstream` expects `char` buffer. Use `reinterpret_cast` and check if by
any chance the `char` type on a platform is implemented with more
than one byte. Then the `reinterpret_cast<char *>(buffer)` would change the
meaning of the `size` parameter, which could lead to garbage data.
Co-authored-by: Reinhold Gschweicher <pyro4hell@gmail.com>
644431cbc4