fixes for the compilation warnings with Sun CC:

1. some fixes for "String literal to char * conversion" warnings (many
   more left in the *.xpm files)
2. fixes for "assignment of function to extern "C" function"
3. a few other miscellaneous ones


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@13478 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/cshelp.cpp

@@ -218,7 +218,7 @@ bool wxContextHelp::DispatchEvent(wxWindow* win, const wxPoint& pt)
  */
 
 #if !defined(__WXMSW__)
-static char * csquery_xpm[] = {
+static const char * csquery_xpm[] = {
 "12 11 2 1",
 "  c None",
 ". c #000000",