Qt 4.8: Remove unused configurations

We don't test mscv2008 anymore.

Change-Id: I126d2122bbe3f033f3867b6e7b947201c58f73c9
Reviewed-by: Simo Fält <simo.falt@digia.com>
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@digia.com>