[Lazarus] Forms.pp function error?

[AlexeyT via Lazarus]

As pointed by Dmitry B, and checked by myself in LCL, MK_ALT must be
defined in LCLType.pp as $20000000. For ex, this is sample from
qtwidgets.pas:

  if (ModifierState and MK_SHIFT) <> 0 then
    Msg.State := [ssShift];
  if (ModifierState and MK_CONTROL) <> 0 then
    Msg.State := [ssCtrl] + Msg.State;
  if (ModifierState and $20000000) <> 0 then
    Msg.State := [ssAlt] + Msg.State;

patch added.