AD7405: Add parametrized make feature and HDL project documentation.

[PopPaul2021]

PR Description

Make can now be performed using the LVDS_CMOS_N parameter, which changes the type of data and clock signals to support the AD7405, AD7403, and ADuM7701. The HDL project documentation has also been added.

PR Type

• [ ] Bug fix (change that fixes an issue)
• [x] New feature (change that adds new functionality)
• [ ] Breaking change (has dependencies in other repos or will cause CI to fail)

PR Checklist

• [x] I have followed the code style guidelines
• [x] I have performed a self-review of changes
• [x] I have compiled all hdl projects and libraries affected by this PR
• [ ] I have tested in hardware affected projects, at least on relevant boards
• [ ] I have commented my code, at least hard-to-understand parts
• [x] I have signed off all commits from this PR
• [x] I have updated the documentation (wiki pages, ReadMe files, Copyright etc)
• [x] I have not introduced new Warnings/Critical Warnings on compilation
• [ ] I have added new hdl testbenches or updated existing ones

[PopPaul2021]

V3: Updates after review

[PIoandan]

Made squash for commits.