overlay-files: Refactor wlan0 ifup Networking Configuration

- Eliminated deprecated `wext` option from the wpa_supplicant invocation to align with contemporary wireless driver standards, preventing wireless network association delays.
- Incorporated a 15-second timeout within udhcpc_opts, ensuring adequate time for the device to aquire a dhcp lease from the network.
- Transitioned all wpa_supplicant parameters to the `pre-up` directive, ensuring wpa_supplicant initialization precedes DHCP client execution.

Collectively, these modifications optimize the DHCP lease acquisition process, enhancing the device's network initialization speed.

general/overlay/etc/network/interfaces.d/wlan0

@@ -1,5 +1,7 @@
+auto wlan0
 iface wlan0 inet dhcp
-    post-up wpa_passphrase "$(fw_printenv -n wlanssid || echo OpenIPC)" "$(fw_printenv -n wlanpass || echo OpenIPC12345)" > /tmp/wpa_supplicant.conf
-    post-up sed -i '2i \\tscan_ssid=1' /tmp/wpa_supplicant.conf
-    post-up wpa_supplicant -B -i wlan0 -D nl80211,wext -c /tmp/wpa_supplicant.conf
+    udhcpc_opts -t 15
+    pre-up wpa_passphrase "$(fw_printenv -n wlanssid || echo OpenIPC)" "$(fw_printenv -n wlanpass || echo OpenIPC12345)" > /tmp/wpa_supplicant.conf
+    pre-up sed -i '2i \\tscan_ssid=1' /tmp/wpa_supplicant.conf
+    pre-up wpa_supplicant -D nl80211 -i wlan0 -c /tmp/wpa_supplicant.conf -B
     post-down killall -q wpa_supplicant

general/overlay/etc/wireless/interfaces/wlan0

@@ -1,6 +1,7 @@
 auto wlan0
 iface wlan0 inet dhcp
-    post-up wpa_passphrase "$(fw_printenv -n wlanssid || echo OpenIPC)" "$(fw_printenv -n wlanpass || echo OpenIPC12345)" > /tmp/wpa_supplicant.conf
-    post-up sed -i '2i \\tscan_ssid=1' /tmp/wpa_supplicant.conf
-    post-up wpa_supplicant -B -i wlan0 -D nl80211,wext -c /tmp/wpa_supplicant.conf
+    udhcpc_opts -t 15
+    pre-up wpa_passphrase "$(fw_printenv -n wlanssid || echo OpenIPC)" "$(fw_printenv -n wlanpass || echo OpenIPC12345)" > /tmp/wpa_supplicant.conf
+    pre-up sed -i '2i \\tscan_ssid=1' /tmp/wpa_supplicant.conf
+    pre-up wpa_supplicant -D nl80211 -i wlan0 -c /tmp/wpa_supplicant.conf -B
     post-down killall -q wpa_supplicant