staging: vt6655: Create one function for two macros

Create function vt6655_mac_set_bits with two parameters to cover
functionality of two macros.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/78883f42b2df258dbf821d7f7515a82932a157f1.1659892670.git.philipp.g.hortmann@gmail.com


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