samples: wifi: monitor: Fix stack overflow in usbd_workq

Fix stack overflow in `usbd_workq` observed after recent upmerge.

Fixes SHEL-3835.

Signed-off-by: Triveni Danda <[email protected]>

Author: D-Triveni

samples/wifi/monitor/overlay-netusb.conf

@@ -1,5 +1,6 @@
 # USB Device settings
 CONFIG_USB_DEVICE_STACK=y
+CONFIG_USB_NRFX_WORK_QUEUE_STACK_SIZE=1200
 
 # Select USB Configurations
 CONFIG_USB_DEVICE_NETWORK_ECM=y