termbits.h: create termbits-common.h for identical bits

Some defines are the same across all archs. Move the most obvious
intersection to termbits-common.h.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220509093446.6677-2-ilpo.jarvinen@linux.intel.com


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