Add @sample to gcm.conf missed when I introduced it. No bump on PORTR…

…EVISION

since GCM is disabled by default

Submitted by:	Jose Luis Duran
Obtained from:	pfsense/FreeBSD-ports#2

security/strongswan/pkg-plist

@@ -253,7 +253,7 @@ man/man8/charon-cmd.8.gz
 %%GCM%%lib/ipsec/plugins/libstrongswan-gcm.a
 %%GCM%%lib/ipsec/plugins/libstrongswan-gcm.la
 %%GCM%%lib/ipsec/plugins/libstrongswan-gcm.so
-%%GCM%%%%ETCDIR%%.d/charon/gcm.conf.sample
+%%GCM%%@sample %%ETCDIR%%.d/charon/gcm.conf.sample
 %%IKEv1%%lib/ipsec/plugins/libstrongswan-xauth-generic.a
 %%IKEv1%%lib/ipsec/plugins/libstrongswan-xauth-generic.la
 %%IKEv1%%lib/ipsec/plugins/libstrongswan-xauth-generic.so