LCL: rename TCMMouseWheel.WheelData to WheelDelta. Issue #24989, patch from Stephano

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42751 4005530d-fff6-0310-9dd1-cebe43e6787f
LCL: Make TWinControl.GetChildren public. Issue #24974, patch from Stephano.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42752 4005530d-fff6-0310-9dd1-cebe43e6787f