Revert "Add new regulatory-domain parameter to cloud-init files"

Existing Ubuntu version does not like new regulatory-domain
parameter being present.
This reverts commit 31252bf.

debian/changelog

@@ -7,7 +7,6 @@ rpi-imager (1.7.3) unstable; urgency=medium
   * Fix ""Cannot send events to objects owned by a different thread" warning
   * Update Slovan/Korean language files
   * Allow selecting file names without extension
-  * Add new regulatory-domain parameter to cloud-init files
   * Add possibility to outsource handling of custom settings to script at
     /usr/lib/raspberrypi-sys-mods/imager_custom
 

src/OptionsPopup.qml

@@ -733,7 +733,6 @@ Popup {
             cloudinitnetwork += "wifis:\n"
             cloudinitnetwork += "  renderer: networkd\n"
             cloudinitnetwork += "  wlan0:\n"
-            cloudinitnetwork += "    regulatory-domain: \""+fieldWifiCountry.editText+"\"\n"
             cloudinitnetwork += "    dhcp4: true\n"
             cloudinitnetwork += "    optional: true\n"
             cloudinitnetwork += "    access-points:\n"
@@ -743,7 +742,9 @@ Popup {
                 cloudinitnetwork += "        hidden: true\n"
             }
 
-            /* legacy */
+            /* FIXME: setting wifi country code broken on Ubuntu
+               For unknown reasons udev does not trigger setregdomain automatically and as a result
+               our setting in /etc/default/crda is being ignored by Ubuntu. */
             addCloudInitRun("sed -i 's/^\s*REGDOMAIN=\S*/REGDOMAIN="+fieldWifiCountry.editText+"/' /etc/default/crda || true")
         }
         if (chkLocale.checked) {