Make enablement of the MMU more flexible

This patch adds a 'flags' parameter to each exception level specific function
responsible for enabling the MMU. At present only a single flag which indicates
whether the data cache should also be enabled is implemented. Subsequent patches
will use this flag when enabling the MMU in the warm boot paths.

Change-Id: I0eafae1e678c9ecc604e680851093f1680e9cefa
diff --git a/include/lib/aarch64/xlat_tables.h b/include/lib/aarch64/xlat_tables.h
index 8e0adc7..2d4a211 100644
--- a/include/lib/aarch64/xlat_tables.h
+++ b/include/lib/aarch64/xlat_tables.h
@@ -31,6 +31,14 @@
 #ifndef __XLAT_TABLES_H__
 #define __XLAT_TABLES_H__
 
+
+/*
+ * Flags to override default values used to program system registers while
+ * enabling the MMU.
+ */
+#define DISABLE_DCACHE		(1 << 0)
+
+#ifndef __ASSEMBLY__
 #include <stdint.h>
 
 /*
@@ -67,7 +75,8 @@
 
 void init_xlat_tables(void);
 
-void enable_mmu_el1(void);
-void enable_mmu_el3(void);
+void enable_mmu_el1(uint32_t flags);
+void enable_mmu_el3(uint32_t flags);
 
+#endif /*__ASSEMBLY__*/
 #endif /* __XLAT_TABLES_H__ */