blk_is_available() returns true iff the BDS is inserted (which means
blk_bs() is not NULL and bdrv_is_inserted() returns true) and if the
tray of the guest device is closed.
blk_is_inserted() is changed to return true only if blk_bs() is not
NULL.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>