[PATCH] powerpc: Kill _machine and hard-coded platform numbers

This removes statically assigned platform numbers and reworks the
powerpc platform probe code to use a better mechanism.  With this,
board support files can simply declare a new machine type with a
macro, and implement a probe() function that uses the flattened
device-tree to detect if they apply for a given machine.

We now have a machine_is() macro that replaces the comparisons of
_machine with the various PLATFORM_* constants.  This commit also
changes various drivers to use the new macro instead of looking at
_machine.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 485be38..1b1f24e 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -75,6 +75,7 @@
 #include "ati_ids.h"
 
 #ifdef __powerpc__
+#include <asm/machdep.h>
 #include <asm/prom.h>
 #include "../macmodes.h"
 #endif
@@ -2516,7 +2517,7 @@
 
 	memset(&var, 0, sizeof(var));
 #ifdef CONFIG_PPC
-	if (_machine == _MACH_Pmac) {
+	if (machine_is(powermac)) {
 		/*
 		 *  FIXME: The NVRAM stuff should be put in a Mac-specific file, as it
 		 *         applies to all Mac video cards
@@ -2671,7 +2672,7 @@
 		return 0;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if ((_machine == _MACH_Pmac) && blank > FB_BLANK_NORMAL)
+	if (machine_is(powermac) && blank > FB_BLANK_NORMAL)
 		set_backlight_enable(0);
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
 	if (par->lcd_table && blank > FB_BLANK_NORMAL &&
@@ -2703,7 +2704,7 @@
 	aty_st_le32(CRTC_GEN_CNTL, gen_cntl, par);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if ((_machine == _MACH_Pmac) && blank <= FB_BLANK_NORMAL)
+	if (machine_is(powermac) && blank <= FB_BLANK_NORMAL)
 		set_backlight_enable(1);
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
 	if (par->lcd_table && blank <= FB_BLANK_NORMAL &&