CMake: Generate config-specific moc parameters file.

When using the visual studio generators, a moc parameters file
for each configuration is generated. The content differs because
the -DQT_NO_DEBUG may be added or not, depending on the configuration.

Change-Id: I52eae536289d451df72df2e4dba709851279694a
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>