layer23: fix parsing of command line options

After the recent refactoring, parsing of the command line options is
broken for some arguments.  Specifically, the value of '-a'/'--arfcn'
is ignored and hard-coded ARFCN=871 is used instead.

The problem is that l23_app_init(), which allocates an MS state and
sets the initial ARFCN, is called *before* handle_options().  So the
cfg_test_arfcn is used before it gets overwritten from the argv[].

The usual approach in osmo-* apps is to parse the command line
arguments first, and only then execute code which depends on
configurable parameters.  Let's follow this approach too.

Change-Id: I77ca11c14561fa3fcb9add60ccea5b0b847a20c4

src/host/layer23/src/common/main.c

@@ -254,14 +254,14 @@ int main(int argc, char **argv)
 
 	print_copyright();
 
+	handle_options(argc, argv);
+
 	rc = l23_app_init();
 	if (rc < 0) {
 		fprintf(stderr, "Failed during l23_app_init()\n");
 		exit(1);
 	}
 
-	handle_options(argc, argv);
-
 	if (l23_app_info.opt_supported & L23_OPT_VTY) {
 		if (_vty_init() < 0)
 			exit(1);

src/host/layer23/src/mobile/main.c

@@ -255,6 +255,12 @@ int main(int argc, char **argv)
 
 	print_copyright();
 
+	rc = handle_options(argc, argv);
+	if (rc) { /* Abort in case of parsing errors */
+		fprintf(stderr, "Error in command line options. Exiting.\n");
+		return 1;
+	}
+
 	srand(time(NULL));
 
 	INIT_LLIST_HEAD(&ms_list);
@@ -272,12 +278,6 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
-	rc = handle_options(argc, argv);
-	if (rc) { /* Abort in case of parsing errors */
-		fprintf(stderr, "Error in command line options. Exiting.\n");
-		return 1;
-	}
-
 	if (custom_cfg_file) {
 		/* Use full path provided by user */
 		config_file = talloc_strdup(l23_ctx, custom_cfg_file);