Fix removing the name of the room
Fix removing the name of the room

The name of the room is removed by setting it to the empty string, but
the if condition was wrong and thus an empty string did not satisfy it.

Signed-off-by: Daniel Calviño Sánchez <bd7629e975cc0e00ea7cda4ab6a120f2ee42ac1b@gmail.com>

nextcloud/spreed,nextcloud/spreed,nextcloud/spreed