staging: vt6655: Rename byRegOfs to reg_offset in four macros

Fix name of a variable in four macros that use CamelCase which is not
accepted by checkpatch.pl

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/82f65d22ac8cd75b2c7790c13be3d0068968925b.1657657918.git.philipp.g.hortmann@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>