control-host: Use fsi-master class paths

As of dev-5.3, and upstream v5.4, the FSI core creates fsi master class
based sysfs paths. These paths do not change depending on the FSI
master implantation or device tree layout, and therefore should be more
stable.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Change-Id: I279024ca73e3f3d87c3456cf4fcd8d54615cd285
1 file changed