Tegra: platform: support Tegra186 chip id

This patch adds support to read the chip id and identify if
the current platform is Tegra186.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/include/tegra_platform.h b/plat/nvidia/tegra/include/tegra_platform.h
index a2813a8..c06ce70 100644
--- a/plat/nvidia/tegra/include/tegra_platform.h
+++ b/plat/nvidia/tegra/include/tegra_platform.h
@@ -42,8 +42,10 @@
 /*
  * Tegra chip identifiers
  */
-uint8_t tegra_is_t132(void);
-uint8_t tegra_is_t210(void);
+uint8_t tegra_chipid_is_t132(void);
+uint8_t tegra_chipid_is_t210(void);
+uint8_t tegra_chipid_is_t186(void);
+
 
 /*
  * Tegra platform identifiers