Pcbnew: cosmetic enhancement: add missing icons to 2 menuitems in "Route" menu

pcbnew/tools/pcb_actions.cpp

@@ -1135,14 +1135,14 @@ TOOL_ACTION PCB_ACTIONS::routerTuneDiffPair( "pcbnew.LengthTuner.TuneDiffPair",
         // Don't be tempted to remove "Modern Toolset only".  It's in the legacy property name.
         '8', LEGACY_HK_NAME( "Tune Differential Pair Length (Modern Toolset only)" ),
         _( "Tune length of a differential pair" ), "",
-        nullptr, AF_ACTIVATE, (void*) PNS::PNS_MODE_TUNE_DIFF_PAIR );
+        ps_diff_pair_tune_length_xpm, AF_ACTIVATE, (void*) PNS::PNS_MODE_TUNE_DIFF_PAIR );
 
 TOOL_ACTION PCB_ACTIONS::routerTuneDiffPairSkew( "pcbnew.LengthTuner.TuneDiffPairSkew",
         AS_GLOBAL,
         // Don't be tempted to remove "Modern Toolset only".  It's in the legacy property name.
         '9', LEGACY_HK_NAME( "Tune Differential Pair Skew (Modern Toolset only)" ),
         _( "Tune skew of a differential pair" ), "",
-        nullptr, AF_ACTIVATE, (void*) PNS::PNS_MODE_TUNE_DIFF_PAIR_SKEW );
+        ps_diff_pair_tune_phase_xpm, AF_ACTIVATE, (void*) PNS::PNS_MODE_TUNE_DIFF_PAIR_SKEW );
 
 TOOL_ACTION PCB_ACTIONS::routerInlineDrag( "pcbnew.InteractiveRouter.InlineDrag",
         AS_CONTEXT, 0, "",