xlat v1: Provide direct MMU-enabling stubs

An earlier patch split MMU-enabling function for translation library v2.
Although we don't intend to introduce the exact same functionality for
xlat v1, this patch introduces stubs for directly enabling MMU to
maintain API-compatibility.

Change-Id: Id7d56e124c80af71de999fcda10f1734b50bca97
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/lib/xlat_tables/aarch64/xlat_tables.c b/lib/xlat_tables/aarch64/xlat_tables.c
index a72c645..5717516 100644
--- a/lib/xlat_tables/aarch64/xlat_tables.c
+++ b/lib/xlat_tables/aarch64/xlat_tables.c
@@ -181,6 +181,11 @@
 									\
 		/* Ensure the MMU enable takes effect immediately */	\
 		isb();							\
+	}								\
+									\
+	void enable_mmu_direct_el##_el(unsigned int flags)		\
+	{								\
+		enable_mmu_el##_el(flags);				\
 	}
 
 /* Define EL1 and EL3 variants of the function enabling the MMU */