WIFI: systemd: add suspend/resume service

For supporting suspend/resume with wifi activate,
brcmfmac MUST be unbinding before each suspend.

Signed-off-by: Christophe Priouzeau <christophe.priouzeau@st.com>

recipes-connectivity/wifi/wifi-suspend/wifi-brcmfmac-sleep.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=Wifi brcmfmac sleep hook
+Before=sleep.target
+StopWhenUnneeded=yes
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=-/usr/bin/wifi_brcmfmac_driver.sh unbind
+ExecStop=-/usr/bin/wifi_brcmfmac_driver.sh bind
+
+[Install]
+WantedBy=sleep.target