#ifdef __alpha__, call a machine-dependent function with new device

structure and 'aux', right before ca_attach is called for the
newly-attached device.  This allows the alpha port to do root device
autodetection without modifying every bus and device driver which could
be in the 'boot path.'  In the long run, it may make sense to make
this machine-independent.

sys/kern/subr_autoconf.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: subr_autoconf.c,v 1.21 1996/04/04 06:06:18 cgd Exp $	*/
+/*	$NetBSD: subr_autoconf.c,v 1.22 1996/06/13 04:50:29 cgd Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993
@@ -352,6 +352,9 @@ config_attach(parent, match, aux, print)
 			if (cf->cf_fstate == FSTATE_STAR)
 				cf->cf_unit++;
 		}
+#ifdef __alpha__
+	device_register(dev, aux);
+#endif
 	(*ca->ca_attach)(parent, dev, aux);
 	return (dev);
 }