meta-digi-dey: Add wifi pre/post actions to suspend script

It has been observed that the wireless interface ocassionally fails to resume
from suspend on extensive long run validation testing, so we workaround it by
bringing the interface down before suspend and bring it up again after resume

This reverts commit a77cd1406d.

https://jira.digi.com/browse/DEL-2217

Signed-off-by: Isaac Hermida <isaac.hermida@digi.com>

meta-digi-dey/recipes-core/busybox/busybox-1.23.2/suspend

@@ -25,6 +25,18 @@ usage() {
 	\n"
 }
 
+suspend_interfaces() {
+	if grep -qs '^wlan0' /var/run/ifstate; then
+		ifdown wlan0 && up_wlan_on_resume="1" && sleep 0.5 && rmmod ath6kl_sdio
+	fi
+}
+
+resume_interfaces() {
+	if ! grep -qs '^wlan0' /var/run/ifstate; then
+		[ -n "${up_wlan_on_resume}" ] && modprobe ath6kl_sdio && sleep 0.5 && ifup wlan0
+	fi
+}
+
 while getopts "h" c; do
 	case "${c}" in
 		h) usage; exit;;
@@ -33,12 +45,14 @@ done
 
 if [ -f "${syspower}" ]; then
 	# Pre-suspend actions
+	suspend_interfaces
 
 	# Suspend the device
 	printf "mem" > ${syspower}
 	sleep .5
 
 	# Post-resume actions
+	resume_interfaces
 else
 	printf "\n[ERROR] File ${syspower} not found\n\n"
 fi