Squish: Fix passing argument to helper function

The code of the helper function has changed and what worked
before by pure coincidence now fell apart.
Passing a list to a function that tries to use it as a key
for a dict results in an exception as lists are not hashable.

The code is likely to change by adding a newer kit. This patch
just makes the current state work without crashing instead of
adding functionality that is not yet used.
Amends aed1616b35.

Change-Id: I6e8a6490988700de14596ba981b5e6900133a79d
Reviewed-by: Robert Loehning <robert.loehning@qt.io>

tests/system/suite_qtquick/tst_qtquick_creation/test.py

@@ -33,10 +33,10 @@ def main():
     available = [("5.6", False), ("5.6", True)]
 
     for qtVersion, controls in available:
-        targ = [Targets.DESKTOP_5_6_1_DEFAULT]
+        targ = Targets.DESKTOP_5_6_1_DEFAULT
         # using a temporary directory won't mess up a potentially existing
         workingDir = tempDir()
-        checkedTargets = createNewQtQuickApplication(workingDir, targets=targ,
+        checkedTargets = createNewQtQuickApplication(workingDir, targets=[targ],
                                                      minimumQtVersion=qtVersion,
                                                      withControls = controls)[0]
         if len(checkedTargets) == 0: