samples: net: wifi: Adding sample.yaml file
samples: net: wifi: Adding sample.yaml file

As the sample.yaml file was missing, then sanitychecker did
not testing any wifi drivers or other wifi related APIs.

Fixes #10389

Signed-off-by: Jukka Rissanen <f9f077d1da4c7aa947f9864fa5a28c3588f6a45d@linux.intel.com>

Vudentz/zephyr,nashif/zephyr,finikorg/zephyr,galak/zephyr,ldts/zephyr,Vudentz/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,punitvara/zephyr,finikorg/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,finikorg/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,punitvara/zephyr,finikorg/zephyr,ldts/zephyr,ldts/zephyr,Vudentz/zephyr,nashif/zephyr,punitvara/zephyr,galak/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,punitvara/zephyr,finikorg/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,explora26/zephyr,explora26/zephyr