actions: Fix memory leak on error path in parse_ct_lb_action().

Found by Coverity.

Reported-at: https://scan3.coverity.com/reports.htm#v16889/p10449/fileInstanceId=14763031&defectInstanceId=4305318&mergedDefectId=180399
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>

ovn/lib/actions.c

@@ -884,6 +884,7 @@ parse_ct_lb_action(struct action_context *ctx)
         while (!lexer_match(ctx->lexer, LEX_T_RPAREN)) {
             if (ctx->lexer->token.type != LEX_T_INTEGER
                 || mf_subvalue_width(&ctx->lexer->token.value) > 32) {
+                free(dsts);
                 lexer_syntax_error(ctx->lexer, "expecting IPv4 address");
                 return;
             }