Move generic architectural setup out of blx_plat_arch_setup().

blx_plat_arch_setup() should only perform platform-specific
architectural setup, e.g. enabling the MMU.  This patch moves
generic architectural setup code out of blx_plat_arch_setup().

Change-Id: I4ccf56b8c4a2fa84909817779a2d97a14aaafab6
diff --git a/bl1/aarch64/bl1_entrypoint.S b/bl1/aarch64/bl1_entrypoint.S
index f5ccc65..9db2bdf 100644
--- a/bl1/aarch64/bl1_entrypoint.S
+++ b/bl1/aarch64/bl1_entrypoint.S
@@ -28,6 +28,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <arch.h>
 
 	.globl	reset_handler
 
@@ -49,6 +50,23 @@
 	 */
 	bl	cpu_reset_handler
 
+	/* ---------------------------------------------
+	 * Set the exception vector to something sane.
+	 * ---------------------------------------------
+	 */
+	adr	x0, early_exceptions
+	msr	vbar_el3, x0
+
+	/* ---------------------------------------------
+	 * Enable the instruction cache.
+	 * ---------------------------------------------
+	 */
+	mrs	x0, sctlr_el3
+	orr	x0, x0, #SCTLR_I_BIT
+	msr	sctlr_el3, x0
+
+	isb
+
 _wait_for_entrypoint:
 	/* ---------------------------------------------
 	 * Find the type of reset and jump to handler