Handle windows line endings and tabs in json config files

Change-Id: I154629d862977dde5232db3bb2597474b6053ffd
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

mkspecs/features/qt_configure.prf

@@ -826,6 +826,8 @@ defineTest(qtRunSingleTest) {
 defineReplace(qtConfEvaluate) {
     isEmpty(1): return(true)
 
+    1 ~= s/$$escape_expand(\\t)/ /g
+    1 ~= s/$$escape_expand(\\r)//g
     1 ~= s/$$escape_expand(\\n) */ /g
     expr = $${1}
     expr ~= s/&&/ && /g