[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/aty128fb.c b/drivers/video/aty/aty128fb.c
index 620c9a9..f07be22 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -67,6 +67,7 @@
 #include <asm/io.h>
 
 #ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
 #include <asm/pmac_feature.h>
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
@@ -1748,7 +1749,7 @@
 
 	var = default_var;
 #ifdef CONFIG_PPC_PMAC
-	if (_machine == _MACH_Pmac) {
+	if (machine_is(powermac)) {
 		/* Indicate sleep capability */
 		if (par->chip_gen == rage_M3) {
 			pmac_call_feature(PMAC_FTR_DEVICE_CAN_WAKE, NULL, 0, 1);
@@ -2011,7 +2012,7 @@
 		return 0;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if ((_machine == _MACH_Pmac) && blank)
+	if (machine_is(powermac) && blank)
 		set_backlight_enable(0);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 
@@ -2029,7 +2030,7 @@
 		aty128_set_lcd_enable(par, par->lcd_on && !blank);
 	}
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if ((_machine == _MACH_Pmac) && !blank)
+	if (machine_is(powermac) && !blank)
 		set_backlight_enable(1);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 	return 0;