WRG: remove a wrg in gdal on vc2010

CMake/CTestCustom.cmake.in

@@ -57,7 +57,8 @@ SET(CTEST_CUSTOM_WARNING_EXCEPTION
   "WARNING non-zero return value in ctest"
   ".*Microsoft.*include.*.h.*[Ww]arning.*"
   ".*gdal_priv.h.*[Ww]arning.*"
-  
+  ".*cpl_string.h.*[Ww]arning.*"
+
   # Ignore clang's summary warning, assuming prior text has matched some
   # other warning expression:
   "[0-9,]+ warnings? generated."