removing avpops module from list of standard modules, as it is unmaintained and all the AVP functionality is already in the core

Makefile

@@ -85,7 +85,7 @@ doc_format?=html
 # Modules in this group are considered a standard part of SER (due to 
 # widespread usage) and have no external compile or link dependencies (note 
 # that some of these interplay with external systems).
-module_group_standard=acc_syslog auth avp avpops ctl dispatcher diversion enum\
+module_group_standard=acc_syslog auth avp ctl dispatcher diversion enum\
 				eval exec fifo flatstore gflags maxfwd mediaproxy \
 				nathelper options pdt permissions pike print ratelimit \
 				registrar rr sanity sl textops timer tm uac unixsock uri \