sensor: iis2mdc: spi: Fix use of deprecated spi_cs_control field
sensor: iis2mdc: spi: Fix use of deprecated spi_cs_control field

The gpio_dev field of struct spi_cs_control is deprecated.  The
driver was already using SPI_CONFIG_DT_INST, so we should be
using the associated gpio member of spi_cs_control.

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

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