Add some helper macros to make #ifdef's in sysinstall easier to read

and more maintainable.
- WITH_SYSCONS: defined on all arch's that support syscons (currently i386,
  alpha, and ia64)
- WITH_MICE: defined on all arch's that support moused(8) (currently i386,
  alpha, and ia64)
- WITH_SLICES: defined on all arch's that use disk slices (currently i386
  and ia64)
- WITH_LINUX: defined on all arch's that support Linux binary compat
  (currently i386 and alpha)

Approved by:	re

usr.sbin/sade/sade.h

@@ -54,9 +54,23 @@
 
 /*** Defines ***/
 
+#if defined(__i386__) || defined(__alpha__) || defined(__ia64__)
+#define	WITH_SYSCONS
+#define	WITH_MICE
+#endif
+
+#if defined(__i386__) || defined(__ia64__)
+#define	WITH_SLICES
+#endif
+
+#if defined(__i386__) || defined(__alpha__)
+#define	WITH_LINUX
+#endif
+
 #if defined(PC98)
 #define PCCARD_ARCH 1		        /* Support PCCARD installations */
 #endif
+
 /* device limits */
 #define DEV_NAME_MAX		64	/* The maximum length of a device name	*/
 #define DEV_MAX			100	/* The maximum number of devices we'll deal with */

usr.sbin/sysinstall/sysinstall.h

@@ -54,9 +54,23 @@
 
 /*** Defines ***/
 
+#if defined(__i386__) || defined(__alpha__) || defined(__ia64__)
+#define	WITH_SYSCONS
+#define	WITH_MICE
+#endif
+
+#if defined(__i386__) || defined(__ia64__)
+#define	WITH_SLICES
+#endif
+
+#if defined(__i386__) || defined(__alpha__)
+#define	WITH_LINUX
+#endif
+
 #if defined(PC98)
 #define PCCARD_ARCH 1		        /* Support PCCARD installations */
 #endif
+
 /* device limits */
 #define DEV_NAME_MAX		64	/* The maximum length of a device name	*/
 #define DEV_MAX			100	/* The maximum number of devices we'll deal with */