Split of architecture-dependent and -independent functions for i386,

mainly in the kernel and headers. This split based on work by
Ingmar Alting <iaalting@cs.vu.nl> done for his Minix PowerPC architecture
port.

 . kernel does not program the interrupt controller directly, do any
   other architecture-dependent operations, or contain assembly any more,
   but uses architecture-dependent functions in arch/$(ARCH)/.
 . architecture-dependent constants and types defined in arch/$(ARCH)/include.
 . <ibm/portio.h> moved to <minix/portio.h>, as they have become, for now,
   architecture-independent functions.
 . int86, sdevio, readbios, and iopenable are now i386-specific kernel calls
   and live in arch/i386/do_* now.
 . i386 arch now supports even less 86 code; e.g. mpx86.s and klib86.s have
   gone, and 'machine.protected' is gone (and always taken to be 1 in i386).
   If 86 support is to return, it should be a new architecture.
 . prototypes for the architecture-dependent functions defined in
   kernel/arch/$(ARCH)/*.c but used in kernel/ are in kernel/proto.h
 . /etc/make.conf included in makefiles and shell scripts that need to
   know the building architecture; it defines ARCH=<arch>, currently only
   i386.
 . some basic per-architecture build support outside of the kernel (lib)
 . in clock.c, only dequeue a process if it was ready
 . fixes for new include files

files deleted:
 . mpx/klib.s - only for choosing between mpx/klib86 and -386
 . klib86.s - only for 86

i386-specific files files moved (or arch-dependent stuff moved) to arch/i386/:
 . mpx386.s (entry point)
 . klib386.s
 . sconst.h
 . exception.c
 . protect.c
 . protect.h
 . i8269.c

include/minix/config.h

@@ -128,7 +128,7 @@
 #define FASTLOAD _FASTLOAD
 
 /* Enable or disable system profiling. */
-#define SPROFILE          0    /* statistical profiling */
+#define SPROFILE          1    /* statistical profiling */
 #define CPROFILE          0    /* call profiling */
 
 #endif /* _CONFIG_H */

include/minix/portio.h

@@ -1,5 +1,5 @@
 /*
-ibm/portio.h
+minix/portio.h
 
 Created:	Jan 15, 1992 by Philip Homburg
 */

include/minix/sys_config.h

@@ -69,6 +69,6 @@ error "_MINIX_MACHINE has incorrect value (0)"
 #endif
 
 /* Kernel debug checks */
-#define DEBUG_LOCK_CHECK 0	/* Interrupt Lock/unlock sanity checking. */
+#define DEBUG_LOCK_CHECK 1	/* Interrupt Lock/unlock sanity checking. */
 
 #endif /* _MINIX_SYS_CONFIG_H */

include/minix/type.h

@@ -136,7 +136,7 @@ struct machine {
   int pc_at;
   int ps_mca;
   int processor;
-  int prot;
+  int padding;	/* used to be protected */
   int vdu_ega;
   int vdu_vga;
 };