[nrf fromtree] drivers: nrf_wifi: Set default stack size of net_mgmt thread

Fixes overflow issue in the net_mgmt thread
during network interface state changes.

Signed-off-by: Triveni Danda <[email protected]>
(cherry picked from commit 3a3f4ab)

Author: D-Triveni

drivers/wifi/nrf_wifi/Kconfig.nrfwifi

@@ -160,6 +160,7 @@ config NRF70_REG_DOMAIN
 # stack requirements.
 config NET_MGMT_EVENT_STACK_SIZE
 	default 2048 if !WIFI_NM_WPA_SUPPLICANT
+	default 4600
 
 config NRF70_LOG_VERBOSE
 	bool "Maintains the verbosity of information in logs"