net: shell: Added missing check for eth iface in "net iface" cmd
net: shell: Added missing check for eth iface in "net iface" cmd

checking if iface is ethernet, before calling ethernet api func

Signed-off-by: Jan Georgi <1d7fb619df63019e2838113a4acecc7f2f6edb9c@lemonbeat.com>
Vudentz/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,nashif/zephyr,finikorg/zephyr,Vudentz/zephyr,nashif/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,galak/zephyr,Vudentz/zephyr,galak/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,nashif/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr