doc: add parasoft tool section to the coding guidelines page

Recently we started to use Parasoft Codescan Static Analysis tool
to fix MISRA violations and align code to follow our Coding Guidelines.
I started fixing violations, and adding suppression tages to fix
false-positive findings. Developers started to ask me, what I'm doing
here and where is the documentation page about that.

Add a new section describing violations fixing process using Parasoft
tool.

Signed-off-by: Maksim Masalski <maksim.masalski@intel.com>