dbus-sdr: set settable state to true if sensor write is enabled

Set the settable state for the sensors to true if
`FEATURE_DYNAMIC_SENSORS_WRITE` is enabled. This will help indicate that
the sensors are writable to the client tools.

Change-Id: I3b61cf5583e697820e28dce3a1d60ea2b08876c2
Signed-off-by: Willy Tu <wltu@google.com>
1 file changed