This changes the behaviour on Win32 somewhat when Windows returned a CURSOR_SUPPRESSED state (touch-screen input hiding cursor globally).
Previously we set IsVisible it to false when CURSOR_SUPPRESSED was set.
Also we handle the CURSOR_SUPPRESSED state slightly different now and still try to hide cursors once when requested.
Reason for the change is that the old behaviour made it harder to recover from touch-screens hiding the cursor because Irrlicht didn't
know anymore which state is _should_ have. This also unifies the behaviour on all drivers as the other drivers already returned the visible
flag independent of the system being able to actually show the cursor.
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6109 dfc29bdd-3216-0410-991c-e03cc46cb475
