fdt: Drop fdt_select.py

This file was used to select between the normal and fallback libfdt
implementations. Now that we only have one, it is not needed.

Drop it and fix up all users.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/fdt_test.py b/tools/binman/fdt_test.py
index df2b0a6..249a9ea 100644
--- a/tools/binman/fdt_test.py
+++ b/tools/binman/fdt_test.py
@@ -12,7 +12,7 @@
 import unittest
 
 import fdt
-from fdt_select import FdtScan
+from fdt import FdtScan
 import fdt_util
 import tools