Autogen: Enable SKIP_UNITY_BUILD_INCLUSION on AUTORCC generated files
rcc
generated files are not compatible with unity builds, because they
contain classes in anonymous namespaces and static data with identical names.
This patch sets the source file property SKIP_UNITY_BUILD_INCLUSION
to On
on all AUTORCC
generated files to exclude them from unity build files.
Fixes: #20191 (closed) "QT5: Exclude resource files from unity build"
Backport: release