frameworks: extend TorchService to be able to handle sysfs torch config

Some devices are still using a sysfs node to control the torch. Let's
support those configurations and properly shut the torch down.

Change-Id: I5fa1cccdcffad26dbfef4b2ee0eafe1218a5308b
Signed-off-by: Roman Birg <roman@cyngn.com>
(cherry picked from commit 204e9e44)