binman: Rename fdt variable to dtb

Since fdt is the name of a module, use a different name for variables to
avoid a conflict.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/control.py b/tools/binman/control.py
index e909678..42d75ef 100644
--- a/tools/binman/control.py
+++ b/tools/binman/control.py
@@ -40,15 +40,15 @@
         images['image'] = Image('image', binman_node)
     return images
 
-def _FindBinmanNode(fdt):
+def _FindBinmanNode(dtb):
     """Find the 'binman' node in the device tree
 
     Args:
-        fdt: Fdt object to scan
+        dtb: Fdt object to scan
     Returns:
         Node object of /binman node, or None if not found
     """
-    for node in fdt.GetRoot().subnodes:
+    for node in dtb.GetRoot().subnodes:
         if node.name == 'binman':
             return node
     return None
@@ -92,8 +92,8 @@
         try:
             tools.SetInputDirs(options.indir)
             tools.PrepareOutputDir(options.outdir, options.preserve)
-            fdt = fdt_select.FdtScan(dtb_fname)
-            node = _FindBinmanNode(fdt)
+            dtb = fdt.FdtScan(dtb_fname)
+            node = _FindBinmanNode(dtb)
             if not node:
                 raise ValueError("Device tree '%s' does not have a 'binman' "
                                  "node" % dtb_fname)
diff --git a/tools/binman/etype/u_boot_dtb_with_ucode.py b/tools/binman/etype/u_boot_dtb_with_ucode.py
index 95405c6..01ee36f 100644
--- a/tools/binman/etype/u_boot_dtb_with_ucode.py
+++ b/tools/binman/etype/u_boot_dtb_with_ucode.py
@@ -44,9 +44,8 @@
             fd.write(self.data)
 
         # Remove the microcode
-        fdt = fdt_select.FdtScan(fname)
-        fdt.Scan()
-        ucode = fdt.GetNode('/microcode')
+        dtb = fdt.FdtScan(fname)
+        ucode = dtb.GetNode('/microcode')
         if not ucode:
             raise self.Raise("No /microcode node found in '%s'" % fname)
 
@@ -64,8 +63,8 @@
                     self.ucode_offset = data_prop.GetOffset() + 12
                     self.ucode_size = len(data_prop.bytes)
         if self.collate:
-            fdt.Pack()
-            fdt.Flush()
+            dtb.Pack()
+            dtb.Flush()
 
             # Make this file the contents of this entry
             self._pathname = fname
diff --git a/tools/binman/func_test.py b/tools/binman/func_test.py
index 7328d03..8960e23 100644
--- a/tools/binman/func_test.py
+++ b/tools/binman/func_test.py
@@ -658,8 +658,8 @@
         fname = tools.GetOutputFilename('test.dtb')
         with open(fname, 'wb') as fd:
             fd.write(second)
-        fdt = fdt_select.FdtScan(fname)
-        ucode = fdt.GetNode('/microcode')
+        dtb = fdt.FdtScan(fname)
+        ucode = dtb.GetNode('/microcode')
         self.assertTrue(ucode)
         for node in ucode.subnodes:
             self.assertFalse(node.props.get('data'))