serial: max310x: replace hardcoded masks with preferred GENMASK()

GENMASK() is preferred when defining bitmasks.

Of all the masks changed, only MAX310x_REV_MASK is actually used.

No functional change.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240118152213.2644269-13-hugo@hugovil.com


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