RPi: Enable caches for rpi2

Now that we have support for running with caches enabled in HYP mode,
opt in to that on the Raspberry Pi 2. This brings a significant performance
boost.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/arm/mach-bcm283x/init.c b/arch/arm/mach-bcm283x/init.c
index d2d366b..4fa94db 100644
--- a/arch/arm/mach-bcm283x/init.c
+++ b/arch/arm/mach-bcm283x/init.c
@@ -15,3 +15,10 @@
 
 	return 0;
 }
+
+#ifdef CONFIG_ARMV7_LPAE
+void enable_caches(void)
+{
+	dcache_enable();
+}
+#endif