TT#38453 Fix f95eeb2: skip new check_origin() on installer stage

Otherwise ngcp-installer failed to install PRO/Carrier as
we build the file /etc/ngcp_mgmt_node the very first time on the first MGMT node:

> +08:22:48 cfg_build_templates
> +08:22:48 cfg_build_configs /etc/ngcp_mgmt_node
> +08:22:48 build_configs=($1)
> +08:22:48 declare -a build_configs
> +08:22:48 log_info 'Generating default configuration files /etc/ngcp_mgmt_node'
> +08:22:48 tee -a /tmp/ngcp-installer.log
> +08:22:48 echo 'Generating default configuration files /etc/ngcp_mgmt_node'
> Generating default configuration files /etc/ngcp_mgmt_node
> +08:22:48 ngcpcfg build /etc/ngcp_mgmt_node
> cat: /etc/ngcp_mgmt_node: No such file or directory
> +08:22:48 log_die 'Error running '\''ngcpcfg build'\'''

Checking the file availability is not enough here, the next error is:

> (sp1)root@sp1:/# ngcpcfg build
> /usr/share/ngcp-ngcpcfg/scripts//check: line 83: NGCP_IS_MGMT: unbound variable
> (sp1)root@sp1:/# cat /etc/default/ngcp-roles
> NGCP_TYPE="sppro"
> (sp1)root@sp1:/#

It happens because /etc/default/ngcp-roles is a fake one at this stage.
Handling NGCP_IS_MGMT properly is also not enough:

> (sp1)root@sp1:/# ngcpcfg build
> 2018-07-16 16:49:32: Error: Remote origin of ngcpcfg is '/mnt/glusterfs/ngcpcfg-share', expected: 'sp:/mnt/glusterfs/ngcpcfg-share'.
> 2018-07-16 16:49:32: Error: NOTE: execute `cd /etc/ngcp-config ; git remote set-url origin 'sp:/mnt/glusterfs/ngcpcfg-share'` to adjust setting.
> 2018-07-16 16:49:32: Error: NOTE: perform `ngcpcfg clean --all` to recreate local master branch from remote.
> (sp1)root@sp1:/#

Which happens because the peer is not yet configured at the moment (first node installation).
Introducing new internal option '--no-check-origin' to skip the test into installer.

Change-Id: I0265c65f45972e92ca92320871a7ef29f8904fec

sbin/ngcpcfg

@@ -126,6 +126,7 @@ case ${1:-} in
   --no-db-sync)    export NO_DB_SYNC=1 ; shift ; "$0" "$@" ;;
   --no-validate)   export NO_VALIDATE=1; shift ; "$0" "$@" ;;
   --no-action-failure) export NO_ACTION_FAILURE=1; shift ; "$0" "$@" ;;
+  --no-check-origin) export NO_CHECK_ORIGIN=1; shift ; "$0" "$@" ;;
   --validate)   export VALIDATE=1; shift ; "$0" "$@" ;;
   -h|--help|help)       usage   ; exit 0;;
   -v|--version|version) version ; exit 0;;

scripts/check

@@ -52,6 +52,11 @@ check_origin() {
     return 0
   fi
 
+  if [ "${NO_CHECK_ORIGIN:-}" = "1" ] ; then
+    log_debug "Skipping check_origin (NO_CHECK_ORIGIN=1)."
+    return 0
+  fi
+
   log_debug "check_origin"
 
   log_debug "cd ${NGCPCTL_MAIN}"