Fix FREQ_BAND for config files

src/scripts/create_ap

@@ -1030,6 +1030,11 @@ read_config() {
         # Read switches and their values
         opt_name="${line%%=*}"
         opt_val="${line#*=}"
+
+        if [[ $opt_name == "FREQ_BAND" ]] ; then
+            FREQ_BAND_SET=1
+        fi
+
         if is_config_opt "$opt_name" ; then
             eval $opt_name="\$opt_val"
         else
@@ -1041,6 +1046,8 @@ read_config() {
 
 ARGS=( "$@" )
 
+FREQ_BAND_SET=0
+
 # Preprocessing for --config before option-parsing starts
 for ((i=0; i<$#; i++)); do
     if [[ "${ARGS[i]}" = "--config" ]]; then
@@ -1059,8 +1066,6 @@ GETOPT_ARGS=$(getopt -o hc:w:g:de:nm: -l "help","hidden","hostapd-debug:","hosta
 [[ $? -ne 0 ]] && exit 1
 eval set -- "$GETOPT_ARGS"
 
-FREQ_BAND_SET=0
-
 while :; do
     case "$1" in
         -h|--help)