wifi: eswifi: spi: Move spi bus into config
wifi: eswifi: spi: Move spi bus into config

Move 'struct spi_dt_spec bus' into the config struct so it
can be const and than possibly placed in ROM.

Signed-off-by: Kumar Gala <383ef5577c6e1178b93f59ec8d0936f76d2a98c4@kernel.org>

galak/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr