OS-dependent sysexts that ship kernel modules, usually also ship the
files in /usr/lib/modules/*-flatcar/modules.XXX When multiple such
sysexts get activated, depmod files from just one sysext win and other
kernel modules cannot be loaded using modprobe. We get around this by
removing the depmod files from every sysext with kernel modules.
Instead, we set up modprobe hook, which dynamically runs depmod in a
temporary directory on every sysext kernel module activation.
Signed-off-by: Daniel Zatovic <daniel.zatovic@gmail.com>