Fix compilation of MSW wxFSVolume with non-wxMSW ports.

There is no way to construct wxIcon from HICON when not using wxMSW, just
leave it unimplemented for non-wxMSW ports.

Closes #14402.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71786 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/volume.cpp

@@ -584,6 +584,7 @@ wxIcon wxFSVolume::GetIcon(wxFSIconType type) const
     wxCHECK_MSG( type >= 0 && (size_t)type < m_icons.GetCount(), wxNullIcon,
                  wxT("wxFSIconType::GetIcon(): invalid icon index") );
 
+#ifdef __WXMSW__
     // Load on demand.
     if (m_icons[type].IsNull())
     {
@@ -621,6 +622,10 @@ wxIcon wxFSVolume::GetIcon(wxFSIconType type) const
     }
 
     return m_icons[type];
+#else
+    wxFAIL_MSG(wxS("Can't convert HICON to wxIcon in this port."));
+    return wxNullIcon;
+#endif
 } // GetIcon
 
 #endif // wxUSE_GUI