PPC: Change lib_ppc/bat_rw.c to use high bats

Currently, this code only deals with BATs 0-3, which makes
it useless on systems that support BATs 4-7.  Add the
support for these registers.

Signed-off-by: Becky Bruce <Becky.bruce@freescale.com>
diff --git a/include/asm-ppc/mmu.h b/include/asm-ppc/mmu.h
index 4f78ca7..59f17de 100644
--- a/include/asm-ppc/mmu.h
+++ b/include/asm-ppc/mmu.h
@@ -140,7 +140,11 @@
 
 typedef enum {
 	IBAT0 = 0, IBAT1, IBAT2, IBAT3,
-	DBAT0, DBAT1, DBAT2, DBAT3
+	DBAT0, DBAT1, DBAT2, DBAT3,
+#ifdef CONFIG_HIGH_BATS
+	IBAT4, IBAT5, IBAT6, IBAT7,
+	DBAT4, DBAT5, DBAT6, DBAT7
+#endif
 } ppc_bat_t;
 
 extern int read_bat(ppc_bat_t bat, unsigned long *upper, unsigned long *lower);