fanctl: Add timeout to dump

Fix an old TODO and only wait for a fan control dump to complete for
30s.  This is over the 25s default D-Bus timeout in case fan control is
hung up on some D-Bus call.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I30c90ce0ada99d2abe304c66db9ee8de433bc7b6
1 file changed