Replace dts includes with C preprocessor syntax

Using the /include/ syntax, the include was evaluated by dtc, only after running
the preprocessor, therefore the .dtsi files were not preprocessed. This patch
adds the #include syntax instead. Evaluating this and preprocessing the files
now happens in a single step, done by the C preprocessor.

Change-Id: I6d0104b6274316fc736e84973502a4d6c2c9d6e0
Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>
diff --git a/fdts/fvp-ve-Cortex-A5x1.dts b/fdts/fvp-ve-Cortex-A5x1.dts
index 0f76601..9d2d1d5 100644
--- a/fdts/fvp-ve-Cortex-A5x1.dts
+++ b/fdts/fvp-ve-Cortex-A5x1.dts
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, Arm Limited. All rights reserved.
+ * Copyright (c) 2019-2020, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -139,6 +139,6 @@
 				<0 0  5 &gic 0  5 4>,
 				<0 0 42 &gic 0 42 4>;
 
-		/include/ "rtsm_ve-motherboard-aarch32.dtsi"
+		#include "rtsm_ve-motherboard-aarch32.dtsi"
 	};
 };