* qemud/qemud.c src/logging.[ch]: Similar as for general libvirt, don't
convert high priority levels to debug level. Ignore LIBVIRT_LOG_FILTERS
and LIBVIRT_LOG_OUTPUTS when they're set to the empty string, otherwise
they can override a valid setting from the config file. Send all
settings through the parser functions for validation, so that the
existence of a bad setting doesn't nullify a good setting that should
have applied -- particularly the default output. Keep the order of
precedence consistent for all variables between the environment and
the config file. Warn when an invalid log level, filter, or output
is ignored.
* src/libvirt_private.syms: export internally a few convenience functions