[bugfix] Put the definition of the 'macroname' variable back in

The 'macroname' variable is still used by the code, but its definition
was accidentally removed together with the AutoTools-generating code.
Therefore, duneproject would fail with

/home/sander/dune/dune-common/bin/duneproject: Zeile 695: dune-foo/cmake/modules/: Ist ein Verzeichnis

This patch puts the missing definition back in.

bin/duneproject

@@ -680,6 +680,13 @@ mkdir "$PROJECT/cmake"
 
 mkdir "$PROJECT/cmake/modules"
 
+macroname=""
+for i in $(echo $PROJECT| sed 's/-/ /g'); do
+  firstchar=$(echo $i | sed 's/\(.\).*/\1/')
+  macroname=$macroname$(echo $firstchar | tr '[a-z]' '[A-Z]')$(echo $i | sed 's/.\(.*\)/\1/')
+done
+macroname="$macroname""Macros.cmake"
+
 ################# cmake/modules/CMakeLists.txt #####################
 
 echo "- $PROJECT/cmake/modules/CMakeLists.txt"