binman: Add a default path to libfdt.py

This module is often available in the sandbox_spl build created by
'make check'. Use this as a default path so that just typing 'binman -t'
(without setting PYTHONPATH) will generally run the tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/binman.py b/tools/binman/binman.py
index 1536e95..f5af535 100755
--- a/tools/binman/binman.py
+++ b/tools/binman/binman.py
@@ -22,6 +22,8 @@
 
 # Bring in the libfdt module
 sys.path.insert(0, 'scripts/dtc/pylibfdt')
+sys.path.insert(0, os.path.join(our_path,
+                '../../build-sandbox_spl/scripts/dtc/pylibfdt'))
 
 import cmdline
 import command
diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py
index 827094e..33b2589 100755
--- a/tools/dtoc/dtoc.py
+++ b/tools/dtoc/dtoc.py
@@ -34,6 +34,11 @@
 our_path = os.path.dirname(os.path.realpath(__file__))
 sys.path.append(os.path.join(our_path, '../patman'))
 
+# Bring in the libfdt module
+sys.path.insert(0, 'scripts/dtc/pylibfdt')
+sys.path.insert(0, os.path.join(our_path,
+                '../../build-sandbox_spl/scripts/dtc/pylibfdt'))
+
 import dtb_platdata
 import test_util