Bump rootfs size for Kinoite installer image to 11
    
    aarch64 ran out of space at size 10:
    https://koji.fedoraproject.org/koji/taskinfo?taskID=118924874
    "The rootfs ran out of space with size=10"
    Let's bump it to 11 for all arches, as the others must be pretty
    close too if aarch64 runs out.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>