dtoc: Fix some minor errors

Fix some comments and a printf string which is incorrect.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/dtoc/dtb_platdata.py b/tools/dtoc/dtb_platdata.py
index b1323ae..6cb1259 100644
--- a/tools/dtoc/dtb_platdata.py
+++ b/tools/dtoc/dtb_platdata.py
@@ -316,7 +316,8 @@
             total = na + ns
 
             if reg.type != fdt.TYPE_INT:
-                raise ValueError("Node '%s' reg property is not an int")
+                raise ValueError("Node '%s' reg property is not an int" %
+                                 node.name)
             if len(reg.value) % total:
                 raise ValueError("Node '%s' reg property has %d cells "
                         'which is not a multiple of na + ns = %d + %d)' %
diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py
index c891b06..2e6a4db 100755
--- a/tools/dtoc/dtoc.py
+++ b/tools/dtoc/dtoc.py
@@ -40,8 +40,8 @@
     """Run all the test we have for dtoc
 
     Args:
-        args: List of positional args provided to binman. This can hold a test
-            name to execute (as in 'binman -t testSections', for example)
+        args: List of positional args provided to dtoc. This can hold a test
+            name to execute (as in 'dtoc -t test_empty_file', for example)
     """
     import test_dtoc
 
diff --git a/tools/dtoc/fdt.py b/tools/dtoc/fdt.py
index c1d04d4..e7703c1 100644
--- a/tools/dtoc/fdt.py
+++ b/tools/dtoc/fdt.py
@@ -428,7 +428,7 @@
         return node
 
 def FdtScan(fname):
-    """Returns a new Fdt object from the implementation we are using"""
+    """Returns a new Fdt object"""
     dtb = Fdt(fname)
     dtb.Scan()
     return dtb