I sometimes see Bison related problems in setting up build environments.
Therefore to remove Bison from build time dependencies, add `y.tab.c`
generated by Bison to the repository.
The reduction of dependency at build time also reduces the labor and time
for setup and installation in CI.
In addition, a path in `#line` directive is converted to a relative path so
that its path is constant regardless of development environments.
KOBAYASHI Shuji