Instead of having separate option for each card and driver use
--audio-drv-list and --audio-card-list options.

Under Linux it allows to set the default(first probed) driver
to something other than OSS.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4792 c046a42c-6fe2-441c-8c8c-71466251a162