[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>

include/asm-powerpc/vdso_datapage.h

@@ -55,6 +55,9 @@ struct vdso_data {
 		__u32 minor;		/* Minor number			0x14 */
 	} version;
 
+	/* Note about the platform flags: it now only contains the lpar
+	 * bit. The actual platform number is dead and burried
+	 */
 	__u32 platform;			/* Platform flags		0x18 */
 	__u32 processor;		/* Processor type		0x1C */
 	__u64 processorCount;		/* # of physical processors	0x20 */