this fixes an assertion failure with qt4 mingw specs when PATH contains
a "." element.
Task-number: QTCREATORBUG-12528
Change-Id: I2b6b7e02cf38881d40bd78bb0d705f7d58d0736c
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
(cherry picked from qtcreator/d0428a05220ed0550dd84cdb8299a1fb37b0fe72)
Reviewed-by: Christian Kandeler <christian.kandeler@theqtcompany.com>