vt: keyboard, use BIT() macro instead of open coded variants

There are few places when BIT() macro is suitable and makes code
easier to understand.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201109105601.47159-1-andriy.shevchenko@linux.intel.com


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