Add support to Adaq4224 and ad4030

[jonathanns]

Pull Request Description

This adds AD4030 and ADAQ4224 features (such as PGIA) to ad463x driver and ad463x_fmcz project. It also adds raw and scale related attributes to IIO.

PR Type

• [x] 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 Coding style guidelines
• [x] I have performed a self-review of the changes
• [x] I have commented my code, at least hard-to-understand parts
• [x] I have build all projects affected by the changes in this PR
• [x] I have tested in hardware affected projects, at the relevant boards
• [x] I have signed off all commits from this PR
• [ ] I have updated the documentation (wiki pages, ReadMe etc), if applies

[jonathanns]

Updates:

• Unrelated changes removed;
• Dropped double/float usage;
• Unnecessary casts removed;
• Fixed Astyle error and misspellings;
• Improved commit body;
• Used another approach in ad463x_iio_read_scale_avail function;
• Fixed other minor problems stated in the review comments;

[jonathanns]

Updates v2:

• Removed find_closest function and replaced by the no_os_util implementation.
• Removed mult_frac implementation.
• Revert DMA and SPI-Engine base address changes to comply with the newest HDL parameters.
• Fix memory leak handling.
• Other minor fixes.
• Tested again with the latest HDL build.

Observation: Axi_pwm needs to be updated to accommodate the new PWM IP that supports up to 16 channels.

[jonathanns]

Updates v3:

• Adressed @rbolboac , @CiprianRegus and @buha comments and sugestions.
• Tested with setup ZedBoard + ADAQ4224.

[rbolboac]

not sure why build did not start, please perform a force-push (no changes needed) to re-trigger the build

[rbolboac]

/AzurePipelines run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).