Changed command line argpasrse to process '--symmetric [True|False]'. (…

…#19577)

### Description
<!-- Describe your changes. -->
Accept the command line option --symmetric and its optional value
correctly. If the optional value matches uncased to 'True' then set
symmetric to True else set symmetric to False. Asymmetric quantization
will generate zero_point input.
```
usage: matmul_4bits_quantizer.py [-h] --input_model INPUT_MODEL --output_model OUTPUT_MODEL [--block_size BLOCK_SIZE] [--symmetric [{True,False}]] [--accuracy_level ACCURACY_LEVEL] [-v]
                                 [--nodes_to_exclude NODES_TO_EXCLUDE [NODES_TO_EXCLUDE ...]]
```
### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->

onnxruntime/python/tools/quantization/matmul_4bits_quantizer.py

@@ -349,6 +349,10 @@ def process(self):
             self.int4_quant_algo()
 
 
+def ort_convert_str_to_bool(value):
+    return value.lower() in ("true", "1")
+
+
 def parse_args():
     parser = argparse.ArgumentParser(
         description="""Blockwise int4 quantization for MatMul 2D weight matrices.
@@ -366,7 +370,10 @@ def parse_args():
         "--symmetric",
         required=False,
         default=True,
-        type=bool,
+        const=True,
+        nargs="?",
+        type=ort_convert_str_to_bool,
+        choices=[True, False],
         help="Indicate whether to quantize the model symmetrically",
     )
     parser.add_argument(