[media] smiapp: Remove smiapp-debug.h in favour of dynamic debug

Remove smiapp-debug.h and let people use CONFIG_DYNAMIC_DEBUG instead. The
option only affected to when debug information was being printed.

Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>