MLBEDSW-6425: Update to TensorFlow 2.8 (bugfix)

Generate flatbuffer files with relative imports.

Signed-off-by: Rickard Bolin <rickard.bolin@arm.com>
Change-Id: Idd59bb2ebb829bc42677920577c1f8a04e23ca68
diff --git a/ethosu/vela/tflite/SparsityParameters.py b/ethosu/vela/tflite/SparsityParameters.py
index 76485f4..5da4692 100644
--- a/ethosu/vela/tflite/SparsityParameters.py
+++ b/ethosu/vela/tflite/SparsityParameters.py
@@ -89,7 +89,7 @@
             x = self._tab.Vector(o)
             x += flatbuffers.number_types.UOffsetTFlags.py_type(j) * 4
             x = self._tab.Indirect(x)
-            from tflite.DimensionMetadata import DimensionMetadata
+            from .DimensionMetadata import DimensionMetadata
             obj = DimensionMetadata()
             obj.Init(self._tab.Bytes, x)
             return obj