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/func_test.py b/tools/binman/func_test.py
index 8960e23..8b4db41 100644
--- a/tools/binman/func_test.py
+++ b/tools/binman/func_test.py
@@ -21,7 +21,7 @@
 import command
 import control
 import entry
-import fdt_select
+import fdt
 import fdt_util
 import tools
 import tout