fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
            f.debug_struct("SpiDma").field("spi", &self.spi).finish()
        }
Formats the `SpiDma` instance for debugging purposes.

This method returns a debug struct with the name "SpiDma" without
exposing internal details.
esp-hal/src/spi/master.rs