[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/include/asm-ppc/machdep.h b/include/asm-ppc/machdep.h
index 2723b42..e1a0a7b 100644
--- a/include/asm-ppc/machdep.h
+++ b/include/asm-ppc/machdep.h
@@ -19,6 +19,18 @@
 struct seq_file;
 struct file;
 
+/*
+ * This is for compatibility with ARCH=powerpc.
+ */
+#define machine_is(x)	__MACHINE_IS_##x
+#define __MACHINE_IS_powermac	0
+#define __MACHINE_IS_chrp	0
+#ifdef CONFIG_PPC_PREP
+#define __MACHINE_IS_prep	1
+#else
+#define __MACHINE_IS_prep	0
+#endif
+
 /* We export this macro for external modules like Alsa to know if
  * ppc_md.feature_call is implemented or not
  */