Fix memory leak in API/CLI to create/modify SR policies

The segment list vector built by the API/CLI is not freed after
SR policy creation or modification.

Change-Id: If439005481cada6c6af7cb560fe7a4381dd49384
Signed-off-by: John Lo <loj@cisco.com>
diff --git a/src/vnet/srv6/sr_api.c b/src/vnet/srv6/sr_api.c
index 17d4821..c37923f 100644
--- a/src/vnet/srv6/sr_api.c
+++ b/src/vnet/srv6/sr_api.c
@@ -114,6 +114,7 @@
 		      segments,
 		      ntohl (mp->sids.weight),
 		      mp->type, ntohl (mp->fib_table), mp->is_encap);
+  vec_free (segments);
 
   REPLY_MACRO (VL_API_SR_POLICY_ADD_REPLY);
 }
@@ -147,6 +148,7 @@
 		      mp->operation,
 		      segments, ntohl (mp->sl_index),
 		      ntohl (mp->sids.weight));
+  vec_free (segments);
 
   REPLY_MACRO (VL_API_SR_POLICY_MOD_REPLY);
 }