Before, root privileges were only needed to set hardware registers, not
to read them.  On some hardware, reading from the wrong place at the
wrong time can hang the machine.  So, to be consistent, root privileges
are required to read registers on all hardware.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>