fixed eventfd_signal for kernels >= 6.8

Fixes #14 and #15 by replacing the version-based check for DMA_BUF necessity. Solves incompatibility with backports in 5.1x.x (RedHat/Debian) kernels.

Amend use of `class_create()` for kernels >= 6.4

Update Changelog, bump version to 1.0-18

Import DMA_BUF symbol namespace for kernels >= 5.16

Fix DMA address truncation in gasket_coherent_buffer

Add udev rule for apex permissions

More Makefile Fixes

Fix makefile, bump versions of modules/deb

Add base documentation

Update Debian files for a clean lintian run.

staging: gasket: Fix inclusion of spinlock.h

Move source to src folder, add gitignore

Update changelog

Update changelog.