Use the new (-no)-wmf-backend configuration option
Use the new (-no)-wmf-backend configuration option

Don't build the wmf backend when configure was executed
with the -no-wmf-backend option.

Change-Id: Ia047137c15c7aac302092e9f77b961c6e584bb86
Reviewed-by: Yoann Lopes <27570619e45a2a46618012b16a29b452c478e806@digia.com>
Reviewed-by: Oswald Buddenhagen <6a8868beda3e139b5ac22b2534a23d3e6ba81819@digia.com>

mer-qt/qtmultimedia,mer-qt/qtmultimedia,mer-qt/qtmultimedia,mer-qt/qtmultimedia,mer-qt/qtmultimedia