samples: drivers: Fix unitialized spi_cfg in spi_fujitsu_fram sample
samples: drivers: Fix unitialized spi_cfg in spi_fujitsu_fram sample

Fixes #19670

Signed-off-by: David Leach <98707a1e43c521c5b5b81e36afef696dde6831a3@nxp.com>

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