void ctl_gfx_controller_configure_8b_spi_protocol(CTL_GFX_CONTROLLER_t *self, CTL_SPI_DEVICE_t *dev, void (*set_dc)(CTL_GFX_CONTROLLER_t *, int));
ctl_gfx_controller_configure_8b_spi_protocol configures the driver self to use 4-wire SPI 8-bit protocol on the device dev with D/C provided as a separate digital output controlled by set_dc.