Add y.tab.c to remove Bison from build dependencies; ref 4ce3997

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.

Author: shuujii