mgt: Move -a(cceptor) and -s(torage) configuration until after VEXT load

... to enable acceptor implementations as extensions (and also allow storage to
make use of manager privileges, but for this we probably need a new or
repurposed STV callback).

One test adjustment was required:

c3.vtc tests invalid -a usage, but did not set up a good working directory. Now
that -a is processed later, the test ran into a working directory error instead
of the expected acceptor error.

bin/varnishd/mgt/mgt_main.c

@@ -624,7 +624,6 @@ main(int argc, char * const *argv)
 	const char *h_arg = "critbit";
 	const char *n_arg = getenv("VARNISH_DEFAULT_N");
 	const char *S_arg = NULL;
-	const char *s_arg = "default,100m";
 	const char *W_arg = NULL;
 	const char *c;
 	char *p;
@@ -791,9 +790,6 @@ main(int argc, char * const *argv)
 	/* Process delayed arguments */
 	VTAILQ_FOREACH(alp, &arglist, list) {
 		switch(alp->arg[0]) {
-		case 'a':
-			MAC_Arg(alp->val);
-			break;
 		case 'f':
 			if (*alp->val != '\0')
 				alp->priv = mgt_f_read(alp->val);
@@ -824,9 +820,6 @@ main(int argc, char * const *argv)
 		case 'r':
 			MCF_ParamProtect(cli, alp->val);
 			break;
-		case 's':
-			STV_Config(alp->val);
-			break;
 		default:
 			break;
 		}
@@ -908,9 +901,23 @@ main(int argc, char * const *argv)
 	vext_copyin(vident);
 	vext_load();
 
-	/* If no -s argument specified, process default -s argument */
+	/* defaults if arguments not present */
 	if (!arg_list_count("s"))
-		STV_Config(s_arg);
+		(void) arg_list_add('s', "default,100m");
+
+	VTAILQ_FOREACH(alp, &arglist, list) {
+		switch(alp->arg[0]) {
+		case 'a':
+			MAC_Arg(alp->val);
+			break;
+		case 's':
+			STV_Config(alp->val);
+			break;
+		default:
+			break;
+		}
+		cli_check(cli);
+	}
 
 	/* Configure CLI and Transient storage, if user did not */
 	STV_Config_Final();

bin/varnishtest/tests/c00003.vtc

@@ -1,5 +1,7 @@
 varnishtest "Check that we fail to start with erroneous -a/-b arguments"
 
+setenv VARNISH_DEFAULT_N ${tmpdir}
+
 # Duplicate -a arguments
 # XXX: this cannot be tested reliably, we tolerate port collision
 shell -err -match "have same address|already in use|Address in use" {