Staging: dt3155: remove unused 32-bit and 8-bit global registers

All of the board 32-bit registers and 8-bit i2c registers are either read before
writing to them or they are just written to with a new value.  There is no reason
to keep a 'local' copy of any of them.

As a first step to removing them, get rid of all the ones that are not used in
the driver.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Scott Smedley <ss@aao.gov.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>