Fix test for debug_and_release_target

This is a fix for a446491a.
The option debug_and_release determines whether the debug/ and release/
subdirectories are used to put *object* files there. The option
debug_and_release_target is used to put the final taget into debug/
and release/ directories.

Merge-request: 745
Reviewed-by: dt <qtc-committer@nokia.com>