Fixed: Removed accidental .gitignore change from this commit to align with upstream

Add upstream greybus module for zephyr project

See merge request gsoc/gsoc.beagleboard.io!56

Added proposals for kernel support for ES9080Q and Bela cape

See merge request gsoc/gsoc.beagleboard.io!55

- More information can be found in the forum [0]

[0]: https://forum.beagleboard.org/t/upstream-greybus-module-for-zephyr/41170



Signed-off-by: Ayush Singh <ayush@beagleboard.org>