djamic

Results 2 issues of djamic

![image](https://github.com/webmin/webmin/assets/5052870/3fc22050-b8f6-4452-ba5f-bbabcf42c8e0) In Debian 12 in installation process used hightely memory using. For fix this need kill process /usr/share/webmin/run-postinstall.pl.

This PR adds support for Linux Kernel 6.8 (tested on Ubuntu 24.04). Key changes: - Fixed `ashmem` to use new shrinker API. - Updated `inode` time accessors for newer kernels....