boards: bl653_dvk: Fix incorrect definition of cs-gpios in spi1

`cs-gpios = <&gpio1 23 0>;` is incorrect, since pin P1.23 does not even
exist in nRF52833. According to schematic, it should be P0.23 and this
CS line should be configured as active low.

Signed-off-by: Andrzej Głąbek <andrzej.glabek@nordicsemi.no>