Add details to soundhw in gnt-instance man
Add details to soundhw in gnt-instance man

Signed-off-by: Chris Schrier <4c47cf7d680cfe718767f9d301f0f689175ac782@google.com>
Reviewed-by: Hrvoje Ribicic <be5828fca31f89218048bec4189e30a581aa65da@google.com>

yiannist/ganeti,grnet/snf-ganeti,ganeti/ganeti,andir/ganeti,leshchevds/ganeti,mbakke/ganeti,andir/ganeti,leshchevds/ganeti,grnet/snf-ganeti,dimara/ganeti,onponomarev/ganeti,yiannist/ganeti,apyrgio/ganeti,ganeti/ganeti,leshchevds/ganeti,ganeti-github-testing/ganeti-test-1,mbakke/ganeti,mbakke/ganeti,bitemyapp/ganeti,yiannist/ganeti,bitemyapp/ganeti,andir/ganeti,ganeti/ganeti,apyrgio/ganeti,onponomarev/ganeti,dimara/ganeti,ganeti-github-testing/ganeti-test-1