Driver development part 2

[betai97]

• Modifications to aesdchar driver to support showing circular buffer via LEDs
• Modifications to aesdchar driver to support pushbutton triggering kernel interrupt clear of circular buffer

DoD:

• Commit showing fully finished driver code
• Image or video of driver working on hw

Blockers: Hardware bringup, Driver development part 1

[betai97]

Finished as of latest commit. There were a bunch of commits... latest is https://github.com/cu-ecen-aeld/assignments-3-and-later-betai97/commit/041e462cc23fe3062609a822ea1a67504967ae6e