syslog -C (shared memory) isn't working with some Android kernels

Created by: ollieparanoid

Reported by NTAuthority in #postmarketOS:

it seems shared memory is disabled in my kernel as syslogd fails when using the ring buffer btw, so I have to start weston manually to get log output from there.. it does see a touch screen however ('logread: can't find syslogd buffer: Function not implemented', and syslogd not running either - and using -C it will just fail)

Also @drebrez reported the same problem earlier. The simple workaround is disabling shared memory for syslog for now (new PR) - we enable -C in /etc/conf.d/syslog in postmarketos-base's post-install script right now.

Additionally we could figure out, if there is a kernel option, that always makes it work, and make sure that it is always enabled (add it to kconfig_check).

Right now this causes weston to be not working for the devices in question, if I understood correctly.