* Fix a link issue issues on Windows, probably related toircular gal<->common dependency.

The fix used in commit 1e4abac57 to build kicad binary does not work for pcb_calculator.
So I used a ugly but basic trick to force linking some undefined functions found in gal lib.
This issue could be msys2 specific.

kicad/CMakeLists.txt

@@ -76,7 +76,7 @@ else()
     target_link_libraries( kicad
         common
         gal
-        common
+        common      #repeated due to a circular dependancy bewteen gal and common
         ${wxWidgets_LIBRARIES}
         ${GDI_PLUS_LIBRARIES}
         )

pcb_calculator/pcb_calculator_frame.cpp

@@ -24,6 +24,7 @@
 #include <pcb_calculator.h>
 #include <UnitSelector.h>
 #include <bitmaps.h>
+#include <geometry/shape_poly_set.h>
 
 
 #define KEYWORD_FRAME_POSX                      wxT( "Pcb_calculator_Pos_x" )
@@ -53,7 +54,6 @@ PCB_CALCULATOR_FRAME::PCB_CALCULATOR_FRAME( KIWAY* aKiway, wxWindow* aParent ) :
     PCB_CALCULATOR_FRAME_BASE( aParent )
 {
     SetKiway( this, aKiway );
-
     m_currTransLine     = NULL;
     m_currTransLineType = DEFAULT_TYPE;
     m_currAttenuator    = NULL;
@@ -61,6 +61,9 @@ PCB_CALCULATOR_FRAME::PCB_CALCULATOR_FRAME( KIWAY* aKiway, wxWindow* aParent ) :
     m_TWMode = TW_MASTER_CURRENT;
     m_TWNested = false;
 
+    SHAPE_POLY_SET dummy;   // A ugly trick to force the linker to include
+                            //some methods in code and avoid link errors
+
     // Populate transline list ordered like in dialog menu list
     const static TRANSLINE_TYPE_ID tltype_list[8] =
     {