Fix missing switch from DISTRO_FEATURES to AGL_FEATURES in the
definition of DEMO_PRELOAD. Also remove the now unused variables
for the old navigation app as cleanup.
Bug-AGL: SPEC-3833
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I39b4d49c0a213f162657f0086b21b81eb0524ab8