Commit 8e5eb1bddc introduced the assumtion that mkspecs are
immediately below the mkspecs directory itself. This is not true for
e.g. unsupported/blackberry-armv7le-qcc.
This commit restores qmake's ability to find the "root" of the mkspecs
collection no matter how deeply the actual mkspecs are nested.
Task-number: QTBUG-24665
Change-Id: I98faaf8e6ae7b8524277aea6c17e685e507e37b3
Reviewed-by: Sean Harmer <sh@theharmers.co.uk>
Reviewed-by: Joerg Bornemann <joerg.bornemann@nokia.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>
2dd6f1467f