Driver for 16550 UART interface

This patch adds driver for the 16550 UART interface. The driver is exposed
as a console, which platforms can use to dump their boot/crash logs.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/Makefile b/Makefile
index d38a283..45341f8 100644
--- a/Makefile
+++ b/Makefile
@@ -212,6 +212,7 @@
 				-Iinclude/drivers		\
 				-Iinclude/drivers/arm		\
 				-Iinclude/drivers/io		\
+				-Iinclude/drivers/ti/uart	\
 				-Iinclude/lib			\
 				-Iinclude/lib/aarch64		\
 				-Iinclude/lib/cpus/aarch64	\