MINOR: vars: make the var() sample fetch keyword depend on nothing

This sample fetch doesn't require any L4 client session in practice, as
get_var() now checks for the session. This is important to remove this
dependency in order to support accessing variables in scope "proc" from
anywhere.

src/vars.c

@@ -864,7 +864,7 @@ REGISTER_POST_DEINIT(vars_deinit);
 
 static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
 
-	{ "var", smp_fetch_var, ARG1(1,STR), smp_check_var, SMP_T_STR, SMP_USE_L4CLI },
+	{ "var", smp_fetch_var, ARG1(1,STR), smp_check_var, SMP_T_STR, SMP_USE_INTRN },
 	{ /* END */ },
 }};