Startup: fix -D option is not repeatable
Startup: fix -D option is not repeatable

The -D option should be repeatable to enable overriding of multiple
configuration options.

Fixes: c622ec7dff1b ("ui: override configuration from command line")
Signed-off-by: Jan Viktorin <3eab6ac54c005c4408f608556a6663b7f2abede7@fit.vutbr.cz>

BeeeOn/server,BeeeOn/server,BeeeOn/server,BeeeOn/server