[Frontend][ArgParse] Compile with default(LLVM) target and build with…

… BYOC(apache#17454)

It is a unique use-case to check the default target(LLVM), though TVM is built with BYOC(MRVL-ON)
The config of Codegen(BYOC) contains default values for configuration/optons, it is extracted
during _generate_codegen_args. In command line processing, validate_target_args checks if there are add-on options and it expects that particular target to be given explicitly in command line.  Here, it is test for default (LLVM) path only, hence validate_target_args need to ignore the codegen's configuration

python/tvm/driver/tvmc/target.py

@@ -179,12 +179,13 @@ def validate_targets(parse_targets, additional_target_options=None):
         )
 
     if additional_target_options is not None:
-        # Add-on target options are passed from codegen's config(BYOC) which has pass_default=True
-        # Eg: --target="llvm"
-        if len(tvm_targets) == 1:
-            return
         for target_name in additional_target_options:
             if not any([target for target in parse_targets if target["name"] == target_name]):
+                # When built with USE_MRVL=ON, add-on target options are passed from MRVL codegen's
+                # config which has pass_default=True, Eg: --target="llvm" cnn.onnx
+                if len(tvm_targets) == 1 && (target_name == 'mrvl'):
+                    return
+
                 first_option = list(additional_target_options[target_name].keys())[0]
                 raise TVMCException(
                     f"Passed --target-{target_name}-{first_option}"