If a target is linked against libraries with cmake
(target_link_libraries) and the libraries are not marked as PRIVATE
they are "exported" and in case a other target is linked against this
target it is also linked against *all* (not private) libraries.
Without declaring private libraries PRIVATE a lot of over linking
(linking against unneeded libraries) was done.
winpr is now always build as single library.
The build option MONOLITHIC_BUILD doesn't influence this behavior anymore.
The only exception is winpr-makecert-tool which is still build as extra
library.
This obsoletes complex_libraries for winpr.