main/sudo: backport patch to fix crash on old kernels

In postmarketOS (which uses Alpine's repositories to a large degree), we unfortunately have many devices that use old kernels without the getrandom() syscall. This backports a merged patch from upstream that works around this by using sudo's own implementation of getentropy() instead of the one from your C standard library as the default on Linux.

Closes #13108 (closed) (testing welcome to verify)