Ensure that all pins are set to their default configuration during sleep mode.
Disable the workaround for FTPAN58 (SPI freezes when transfering a single byte) at the end of the transfer. This disables the resources needed for the workaround.
Those changes reduce the power usage by 430-490µA.
Don't use relative imports like `../foo.h` as those depend on the
relative position of both files. Rather than that use imports relative
to the `src` directory, which explicitly is part of the include
directories.
