Report error when qt ios is built with debug only

Doing only debug build is not supported at the moment.
Add error to configure.

Task-number: QTBUG-71990
Change-Id: If35d00c3f09d733efe63d5ea66d07e4a3ec922cc
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

configure.json

@@ -1457,6 +1457,11 @@ Configure with '-qreal float' to create a build that is binary-compatible with 5
         {
             "type": "emccVersion",
             "condition": "config.wasm"
+        },
+        {
+            "type": "error",
+            "condition": "config.ios && features.debug && !features.debug_and_release",
+            "message": "Debug build wihtout Release build is not currently supported on ios see QTBUG-71990. Use -debug-and-release."
         }
     ],