Revert reversion of TensorFlow 2.9 update

With the errors caused by the previous TensorFlow 2.9 update
being fixed, we can proceed with the upgrade.

Signed-off-by: erik.andersson@arm.com <erik.andersson@arm.com>
Change-Id: Ie1f025e8d984efaebc68b8d051126d49bee6b2b8
diff --git a/ethosu/vela/tflite/Rfft2dOptions.py b/ethosu/vela/tflite/Rfft2dOptions.py
index ab91a88..f4f2bf3 100644
--- a/ethosu/vela/tflite/Rfft2dOptions.py
+++ b/ethosu/vela/tflite/Rfft2dOptions.py
@@ -3,36 +3,20 @@
 # namespace: tflite
 
 import flatbuffers
-from flatbuffers.compat import import_numpy
-np = import_numpy()
 
 class Rfft2dOptions(object):
     __slots__ = ['_tab']
 
     @classmethod
-    def GetRootAs(cls, buf, offset=0):
+    def GetRootAsRfft2dOptions(cls, buf, offset):
         n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
         x = Rfft2dOptions()
         x.Init(buf, n + offset)
         return x
 
-    @classmethod
-    def GetRootAsRfft2dOptions(cls, buf, offset=0):
-        """This method is deprecated. Please switch to GetRootAs."""
-        return cls.GetRootAs(buf, offset)
-    @classmethod
-    def Rfft2dOptionsBufferHasIdentifier(cls, buf, offset, size_prefixed=False):
-        return flatbuffers.util.BufferHasIdentifier(buf, offset, b"\x54\x46\x4C\x33", size_prefixed=size_prefixed)
-
     # Rfft2dOptions
     def Init(self, buf, pos):
         self._tab = flatbuffers.table.Table(buf, pos)
 
-def Start(builder): builder.StartObject(0)
-def Rfft2dOptionsStart(builder):
-    """This method is deprecated. Please switch to Start."""
-    return Start(builder)
-def End(builder): return builder.EndObject()
-def Rfft2dOptionsEnd(builder):
-    """This method is deprecated. Please switch to End."""
-    return End(builder)
\ No newline at end of file
+def Rfft2dOptionsStart(builder): builder.StartObject(0)
+def Rfft2dOptionsEnd(builder): return builder.EndObject()