BaseTools: Eot tool Python3 adaption

BaseTools: Eot tool Python3 adaption

v2:
The python files under CParser4 are generated by antlr4 and for
python3 usage. They have python3 specific syntax, for example
the data type declaration for the arguments of a function. That
is not compitable with python2. this patch is to remove these syntax.

Eot tool Python3 adaption.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Liming Gao <liming.gao@intel.com>