Label /usr/lib/sudo/sesh as shell_exec_t
xserver: add lightdm file contexts
userdomain: no longer allow unprivileged users to read kernel symbols

Unprivileged users don't need to read kallsyms and /boot/System.map.

This allow rule was introduced in the initial revision of userdomain.if in
2005, with commit b16c6b8c32a631a2e66265f6f60b664222760972:

    # cjp: why?
    bootloader_read_kernel_symbol_table($1_t)