Voicemail : Redundant value boxnumber is removed

Voicemail : boxnumber under extension{i} was redundant and is removed.

Earlier "config_foreach configure_voicemail extension" was used , which added 4(one for each call) instances of "VoiceMailMain" in extensions.conf.Since we can get value of voice_mail_enable from line ,using line to check value of voice_mail_enable.

Voice mail deposit and retrieve is tested. With multiple line changing voice_mail_enable (1/0 )functionality is tested.

net/asterisk/files/iopsys/lib/voice/config_asterisk.sh

@@ -1691,7 +1691,7 @@ configure_tel_line() {
 
 configure_voicemail() {
 	local extension
-        config_get featureset $1 feature_set
+        config_get featureset $1 calling_features
         if [ -n "$featureset" ]; then
             config_get voice_mail_enable $featureset voice_mail_enable
               if [ -n "$voice_mail_enable" -a "$voice_mail_enable" == "1" ]; then