libfdt: Minor changes to enable TF integration

* Add libfdt.mk helper makefile
* Remove unused libfdt files
* Minor changes to fdt.h and libfdt.h to make them C99 compliant

Adapted from 754d78b1b331b07456c6ea439e401402a186c626.

Change-Id: I0847f1c2e6e11f0c899b0b7ecc522c0ad7de210c
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/lib/libfdt_updated/fdt.h b/lib/libfdt_updated/fdt.h
index 526aedb..c833dc1 100644
--- a/lib/libfdt_updated/fdt.h
+++ b/lib/libfdt_updated/fdt.h
@@ -52,8 +52,16 @@
  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+/*
+ * Portions copyright (c) 2016-2017, ARM Limited and Contributors.
+ * All rights reserved.
+ */
+
 #ifndef __ASSEMBLY__
 
+#include <libfdt_env.h>
+
+
 struct fdt_header {
 	fdt32_t magic;			 /* magic word FDT_MAGIC */
 	fdt32_t totalsize;		 /* total size of DT block */
@@ -80,14 +88,14 @@
 
 struct fdt_node_header {
 	fdt32_t tag;
-	char name[0];
+	char name[];
 };
 
 struct fdt_property {
 	fdt32_t tag;
 	fdt32_t len;
 	fdt32_t nameoff;
-	char data[0];
+	char data[];
 };
 
 #endif /* !__ASSEMBLY */