realtime.in: Fix shellcheck issue

Author: hdiethelm

scripts/realtime.in

@@ -101,7 +101,7 @@ CheckConfig(){
             ;;
     esac
     for  MOD in $MODULES ; do
-        eval MOD=\${MODPATH_"$MOD"}
+        eval MOD="\${MODPATH_${MOD}}"
         if [ -z "$MOD" ]; then continue; fi
         if [ -L "$MOD" ]; then
             MOD=${MOD%/*}/$(readlink "$MOD")