Kconfig options that enable I2C and SPI instances are no longer used
in nRF drivers. Remove all assignments done to these options in related
board definitions, samples, and tests.
For nrf52_pca20020, also no longer needed setting of default values
for GPIO_SX1509B* options is removed (now the gpio_sx1509b driver is
enabled by default when a corresponding devicetree node is enabled).
Signed-off-by: Andrzej Głąbek <andrzej.glabek@nordicsemi.no>
0b300da221