[Feature Request] Enable 'tools-multicall' meson build configuration option

LXC 6.0 added a tools-multicall option which,

...can be used to produce a single lxc binary which can then have all other lxc-XYZ commands be symlinked to. This allows for a massive disk space reduction, particularly useful for embedded platforms.

Space usages:

without tools-multicall:
% du -s orig
4444    orig
with tools-multicall:
% du -s patch
4360    patch