Fix bug with out of range date in wxMSW wxDatePickerCtrl under XP too.

Fix bug with out of range date in wxMSW wxDatePickerCtrl under XP too.

The bug fix of r67990 relied on DateTime_SetSystemtime() returning FALSE if
setting the date failed but, unfortunately, this function doesn't behave
correctly under XP (and presumably earlier systems) and returns TRUE even if
it didn't actually change the date because it was out of range.

Implement an alternative solution not relying on this function return value
but simply checking the range ourselves.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68027 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775