[POWERPC] Spelling fixes: arch/ppc/

Spelling fixes in arch/ppc/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/ppc/platforms/mbx.h b/arch/ppc/platforms/mbx.h
index fe81ca4..1cf36fa 100644
--- a/arch/ppc/platforms/mbx.h
+++ b/arch/ppc/platforms/mbx.h
@@ -37,7 +37,7 @@
 
 /* Memory map for the MBX as configured by EPPC-Bug.  We could reprogram
  * The SIU and PCI bridge, and try to use larger MMU pages, but the
- * performance gain is not measureable and it certainly complicates the
+ * performance gain is not measurable and it certainly complicates the
  * generic MMU model.
  *
  * In a effort to minimize memory usage for embedded applications, any