[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/matrox/matroxfb_base.c b/drivers/video/matrox/matroxfb_base.c
index 951c997..23c1827 100644
--- a/drivers/video/matrox/matroxfb_base.c
+++ b/drivers/video/matrox/matroxfb_base.c
@@ -115,6 +115,7 @@
 #include <asm/uaccess.h>
 
 #ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
 unsigned char nvram_read_byte(int);
 static int default_vmode = VMODE_NVRAM;
 static int default_cmode = CMODE_NVRAM;
@@ -1833,7 +1834,7 @@
 	/* FIXME: Where to move this?! */
 #if defined(CONFIG_PPC_PMAC)
 #ifndef MODULE
-	if (_machine == _MACH_Pmac) {
+	if (machine_is(powermac)) {
 		struct fb_var_screeninfo var;
 		if (default_vmode <= 0 || default_vmode > VMODE_MAX)
 			default_vmode = VMODE_640_480_60;