[9fans] vesa blanking

[erik quanstrom]

this trivial code implements blanking for vesa.

- erik

----

; diffy -c vgavesa.c
/n/dump/2009/1209/sys/src/9/pc/vgavesa.c:157,162 - vgavesa.c:157,182
        }
  }
  
+ static void
+ vesablank(VGAscr *scr, int blank)
+ {
+       Ureg u;
+ 
+       vbesetup(&u, 0x4f10);
+       if(blank)
+               u.bx = 0x0101;
+       else
+               u.bx = 0x0001;
+       vbecall(&u);
+ }
+ 
+ static void
+ vesadrawinit(VGAscr *scr)
+ {
+       scr->blank = vesablank;
+       hwblank = 1;
+ }
+ 
  VGAdev vgavesadev = {
        "vesa",
        0,
/n/dump/2009/1209/sys/src/9/pc/vgavesa.c:163,169 - vgavesa.c:183,189
        0,
        0,
        vesalinear,
-       0,
+       vesadrawinit,
        0,
        0,
        0,