- Changed the configure check for qwt to include qwt6.

git-svn-id: https://openmodelica.org/svn/OpenModelica/trunk@12440 f25d12d1-65f4-0310-ae8a-bbce733d8d8e

configure.in

@@ -497,7 +497,7 @@ if test -n "$QMAKE"; then
     done
     echo $with_qwt | grep -q -- -qt4 && with_qwt_suffix="-qt4"
     with_qwt_res=$with_qwt
-    grep -q 'QWT_VERSION *0x05@<:@0-9@:>@\{4\}$' "$with_qwt/qwt_global.h" || with_qwt="bad"
+    grep -q 'QWT_VERSION *0x0@<:@5-6@:>@@<:@0-9@:>@\{4\}$' "$with_qwt/qwt_global.h" || with_qwt="bad"
   fi
 
   if test x"$with_qwt" = "xno"; then