presence: Add service file to repo

This adds the fan presence service files, one for YAML mode and a
different one for JSON mode, to the repository.  Which one is installed
is based on the --enable-json value.

The JSON mode service file is designed to start as part of the system
reaching the multi-user target.  The YAML mode service file is designed
to start when the chassis is powered on.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Ifd65c98a0d8eab83a06c303221e4b4c69c4a0f7b
4 files changed