Make output of generate_operator_out reproducible

As part of using python_binary_host, argv[0] is often the extracted
python script in a temporary directory. Just hardcode the
generate_operator_out.py name so that a random directory isn't encoded
in the output.

Test: m art_compiler_operator_srcs; inspect output
Change-Id: Ie2a875a1ab288bd56577b2451d4f3e6e0ad70032
diff --git a/tools/generate_operator_out.py b/tools/generate_operator_out.py
index 3bd62fe..73e96fe 100755
--- a/tools/generate_operator_out.py
+++ b/tools/generate_operator_out.py
@@ -183,7 +183,7 @@
   print('')
 
   for enum_name in _ENUMS:
-    print('// This was automatically generated by %s --- do not edit!' % sys.argv[0])
+    print('// This was automatically generated by art/tools/generate_operator_out.py --- do not edit!')
 
     namespaces = _NAMESPACES[enum_name].split('::')
     for namespace in namespaces: