Deprecate second parameter of wxSlider::SetTickFreq().

This parameter was never needed nor properly documented. Simply remove it from
SetTickFreq() and keep the overload still taking it for backwards
compatibility only.

Closes #12907.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66844 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/os2/slider.h

@@ -94,9 +94,6 @@ public:
                                   );
                  void SetThumbLength(int nLen) ;
                  void SetTick(int ntickPos) ;
-                 void SetTickFreq( int n
-                                  ,int nPos
-                                 );
 
     //
     // IMPLEMENTATION
@@ -148,6 +145,10 @@ protected:
                            ,int  nHeight
                            ,int  nSizeFlags = wxSIZE_AUTO
                           );
+
+    // Platform-specific implementation of SetTickFreq
+    virtual void DoSetTickFreq(int freq);
+
 private:
     DECLARE_DYNAMIC_CLASS(wxSlider)
 }; // end of CLASS wxSlider