mount: correct mount man page default iso9660 permission

The mount man page said the default permissions are read for
everyone, but it is in fact, read and execute.

Signed-off-by: Phillip Susi <psusi@ubuntu.com>
mkswap: remove cruft from the man page

I don't think there's any reason to continue to mention behavior
of kernels older than 10 years.

Signed-off-by: Phillip Susi <psusi@ubuntu.com>