Misc. minor fixes and adjustments

[Daniel-Cortez]

What this PR does / why we need it:

This PR does the following:

• Removes duplicate functions from sc1.c. These functions are already present in libpawncc.c, so the ones in sc1.c are never used.
• Updates descriptions for a few variables and functions.
• Other minor adjustments.

Which issue(s) this PR fixes:

Fixes #

What kind of pull this is:

• [ ] A Bug Fix
• [ ] A New Feature
• [ ] Some repository meta (documentation, etc)
• [x] Other

Additional Documentation: