fix vimrc to actually only trigger where it should

.vimrc

@@ -1,9 +1,10 @@
 " source this file in your .vimrc to get the correct editor settings
 " for openQA
+let s:loc = expand('<sfile>:p:h')
 function! ProjectOpenQA()
     " execute only if this function is called for files in the
     " openQA directory
-    if stridx(expand('%:p'), expand('<sfile>:p:h')) == 0
+    if stridx(expand('%:p'), s:loc) == 0
         set expandtab textwidth=0 shiftwidth=4
     endif
 endfunction