Remove duplicated code: core-coder front pre-procesing

• Related issues: #2339 (closed)
• Requested reviewers:

Reason why this change is needed

• The core-coder duplicates several functions in the front pre-processing.

Description of the change

• Harmonizes core-coder duplicates of the front pre-processing functions.
• Remove malloc()/free() from the front pre-processing.
• Remove DEBUG_FORCE_DIR to follow FLP.
• Removes cca 900 lines of source code.

Affected operating points

• All is BE.