This commit removes our dependency on the class "noVNC_touch" which was
set by Javascript. Instead, we can use the CSS media query
"any-pointer: coarse", which means that any pointing device that isn't
accurate is available. In practice this seems to basically be equal to
that a touch screen is available.
This change lets us simplify the selectors in many cases as well, which
is a nice bonus.
f1550c69d9