fdt: Drop fdt_fallback library

Drop this now-unused library and associated tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/dtoc/fdt_select.py b/tools/dtoc/fdt_select.py
index ea78c52..54a3ef2 100644
--- a/tools/dtoc/fdt_select.py
+++ b/tools/dtoc/fdt_select.py
@@ -6,31 +6,13 @@
 # SPDX-License-Identifier:      GPL-2.0+
 #
 
-import fdt_fallback
-
 # Bring in either the normal fdt library (which relies on libfdt) or the
 # fallback one (which uses fdtget and is slower). Both provide the same
 # interface for this file to use.
-try:
-    import fdt_normal
-    have_libfdt = True
-except ImportError:
-    have_libfdt = False
+import fdt_normal
 
-force_fallback = False
-
-def FdtScan(fname, _force_fallback=False):
+def FdtScan(fname):
     """Returns a new Fdt object from the implementation we are using"""
-    if have_libfdt and not force_fallback and not _force_fallback:
-        dtb = fdt_normal.FdtNormal(fname)
-    else:
-        dtb = fdt_fallback.FdtFallback(fname)
+    dtb = fdt_normal.FdtNormal(fname)
     dtb.Scan()
     return dtb
-
-def UseFallback(fallback):
-    global force_fallback
-
-    old_val = force_fallback
-    force_fallback = fallback
-    return old_val