serial: Add Tegra2 serial port support

Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/include/serial.h b/include/serial.h
index 15ab73c..f21d961 100644
--- a/include/serial.h
+++ b/include/serial.h
@@ -27,7 +27,8 @@
     defined(CONFIG_405EP) || defined(CONFIG_405EZ) || defined(CONFIG_405EX) || \
     defined(CONFIG_MB86R0x) || defined(CONFIG_MPC5xxx) || \
     defined(CONFIG_MPC83xx) || defined(CONFIG_MPC85xx) || \
-    defined(CONFIG_MPC86xx) || defined(CONFIG_SYS_SC520)
+    defined(CONFIG_MPC86xx) || defined(CONFIG_SYS_SC520) || \
+    defined(CONFIG_TEGRA2)
 extern struct serial_device serial0_device;
 extern struct serial_device serial1_device;
 #if defined(CONFIG_SYS_NS16550_SERIAL)