call_center: deploy scenario file at install

Deploy the scenario_callcenter.xml b2b scenario file at install.

Thanks go to cleberb on GitHub for reporting this!
Close #1464

(cherry picked from commit a6d681c)

modules/call_center/Makefile

@@ -7,3 +7,10 @@ NAME=call_center.so
 LIBS= 
 
 include ../../Makefile.modules
+
+CALL_CENTER_SCENARIO ?= scenario_callcenter.xml
+
+install_module_custom:
+	mkdir -p $(cfg_prefix)/$(cfg_dir); \
+	$(INSTALL_TOUCH) $(cfg_prefix)/$(cfg_dir)/`basename $(CALL_CENTER_SCENARIO)`; \
+	$(INSTALL_CFG) $(CALL_CENTER_SCENARIO) $(cfg_prefix)/$(cfg_dir)/`basename $(CALL_CENTER_SCENARIO)`; \