Add gitignore
Add gitignore

Change-Id: I24dc395e7eabc2f38e66d7d911b65393324494d7
Signed-off-by: Brad Bishop <713d098c0be4c8fd2bf36a94cd08699466677ecd@fuzziesquirrel.com>

openbmc/phosphor-hwmon,openbmc/phosphor-hwmon