gbproxy: Only route to an SGSN if the BVC is not blocked

Change-Id: I0b54813c04bae2c63975082ad2dacae8affd3127
diff --git a/src/gb_proxy.c b/src/gb_proxy.c
index 69a58d4..c2b958a 100644
--- a/src/gb_proxy.c
+++ b/src/gb_proxy.c
@@ -348,6 +348,8 @@
 			continue;
 		if (sgsn->nse != sgsn_bvc->nse)
 			continue;
+		if (!bssgp_bvc_fsm_is_unblocked(sgsn_bvc->fi))
+			continue;
 
 		return sgsn_bvc;
 	}