[TFLite][Frontend] Support quantized ELU (#15821)

* add quantized elu

* add tests for quantized elu

Author: tlopex

python/tvm/relay/frontend/tflite.py

@@ -1275,8 +1275,6 @@ def convert_neg(self, op):
 
     def convert_elu(self, op):
         """Convert TFLite ELU"""
-        if self.is_quantized(op):
-            raise tvm.error.OpNotImplemented("TFlite quantized ELU operator is not supported yet.")
         input_tensors = self.get_input_tensors(op)
         assert len(input_tensors) == 1, "input tensors length should be 1"
 

tests/python/frontend/tflite/test_forward.py

@@ -2436,7 +2436,7 @@ def test_all_unary_elemwise():
         # from the converter that we need to provide a custom Tan operator
         # implementation.
         # _test_forward_unary_elemwise(_test_tan)
-        _test_forward_unary_elemwise(_test_elu, quantized=False)
+        _test_forward_unary_elemwise(_test_elu)
 
 
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