fix for GTK+ version check caching (now it actually works)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@10757 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

configure.in

@@ -1631,6 +1631,11 @@ if test "$wxUSE_GUI" = "yes"; then
                 if test -z "$wx_cv_lib_gtk"; then
                     dnl looks better in AC_MSG_RESULT
                     wx_cv_lib_gtk=none
+                else
+                    dnl we need to cache GTK_CFLAGS and GTK_LIBS for the
+                    dnl subsequent runs
+                    wx_cv_cflags_gtk=$GTK_CFLAGS
+                    wx_cv_libs_gtk=$GTK_LIBS
                 fi
             ]
         )
@@ -1657,8 +1662,8 @@ equivalent variable and GTK+ is version 1.2.3 or above.
                     ;;
         esac
 
-        TOOLKIT_INCLUDE="$GTK_CFLAGS"
-        GUI_TK_LIBRARY="$GTK_LIBS"
+        TOOLKIT_INCLUDE="$wx_cv_cflags_gtk"
+        GUI_TK_LIBRARY="$wx_cv_lib_gtk"
 
         AFMINSTALL=afminstall
         TOOLKIT=GTK