[microNPU] removing extra bytes for workspace (apache#9629)

Given that microNPU codegen uses target hooks
it undergoes the core compiler that updates
workspace sizes. We dont need the additional
sizes anymore. This commit removes the sizes.

Change-Id: Ifd2a01e5f9566ee0c37778f32392d6d1f8c7c091

tests/python/contrib/test_ethosu/infra.py

@@ -222,7 +222,7 @@ def build_source(module, inputs, outputs, accel="ethos-u55-256", output_toleranc
             inputs=inputs,
             outputs=outputs,
             output_tolerance=output_tolerance,
-            extra_memory_in_bytes=16 * 1024 * 1024,
+            extra_memory_in_bytes=0,
         ),
         interface_api="c",
         use_unpacked_api=True,