Tegra: platform specific BL31_SIZE

This patch moves the BL31_SIZE to the Tegra SoC specific
tegra_def.h. This helps newer platforms configure the size of
the memory available for BL31.

Signed-off-by: anzhou <anzhou@nvidia.com>
Change-Id: I43c60b82fa7e43d5b05d87fbe7d673d729380d82
diff --git a/plat/nvidia/tegra/include/t186/tegra_def.h b/plat/nvidia/tegra/include/t186/tegra_def.h
index 33b2102..a971cec 100644
--- a/plat/nvidia/tegra/include/t186/tegra_def.h
+++ b/plat/nvidia/tegra/include/t186/tegra_def.h
@@ -11,6 +11,11 @@
 #include <lib/utils_def.h>
 
 /*******************************************************************************
+ * Platform BL31 specific defines.
+ ******************************************************************************/
+#define BL31_SIZE			U(0x40000)
+
+/*******************************************************************************
  * MCE apertures used by the ARI interface
  *
  * Aperture 0 - Cpu0 (ARM Cortex A-57)