when Qt4 based qca is installed, okular tries to link against it including -lQt4::QtCore to the linker command. included patch fixes it with qca-2.1.0.3 installed

Reproducible: Always

Steps to Reproduce:
1. install Qt4 based qca
2. compile okular on framworks branch

Actual Results:  
linker error:

Linking CXX shared module okularGenerator_ooo.so
cd /var/tmp/portage/kde-apps/okular-5.9999/work/okular-5.9999_build/generators/ooo && /usr/bin/cmake -E cmake_link_script CMakeFiles/okularGenerator_ooo.dir/link.txt --verbose=1
/usr/bin/x86_64-pc-linux-gnu-g++  -fPIC -march=native -O3 -w -fomit-frame-pointer  -std=c++0x -fno-exceptions -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wnon-virtual-dtor -Woverloaded-virtual -Werror=return-type -Wl,--no-undefined -Wl,--fatal-warnings -Wl,--enable-new-dtags  -Wl,-O1 -Wl,--as-needed -shared -Wl,-soname,okularGenerator_ooo.so -o okularGenerator_ooo.so CMakeFiles/okularGenerator_ooo.dir/converter.cpp.o CMakeFiles/okularGenerator_ooo.dir/document.cpp.o CMakeFiles/okularGenerator_ooo.dir/formatproperty.cpp.o CMakeFiles/okularGenerator_ooo.dir/generator_ooo.cpp.o CMakeFiles/okularGenerator_ooo.dir/manifest.cpp.o CMakeFiles/okularGenerator_ooo.dir/styleinformation.cpp.o CMakeFiles/okularGenerator_ooo.dir/styleparser.cpp.o CMakeFiles/okularGenerator_ooo.dir/okularGenerator_ooo_automoc.cpp.o ../../libokularcore.so.6.0.0 /usr/lib64/libqca.so.2.1.0 /usr/lib64/libKF5Archive.so.5.6.0 /usr/lib64/libKF5JSApi.so.5.6.0 /usr/lib64/libKF5JS.so.5.6.0 /usr/lib64/libKF5KDELibs4Support.so.5.6.0 /usr/lib64/libKF5Crash.so.5.6.0 /usr/lib64/libKF5KIOFileWidgets.so.5.6.0 /usr/lib64/libKF5Bookmarks.so.5.6.0 /usr/lib64/libKF5Solid.so.5.6.0 /usr/lib64/libKF5UnitConversion.so.5.6.0 /usr/lib64/libKF5Parts.so.5.6.0 /usr/lib64/libKF5Notifications.so.5.6.0 /usr/lib64/libKF5KIOWidgets.so.5.6.0 /usr/lib64/libKF5KIOCore.so.5.6.0 /usr/lib64/libKF5JobWidgets.so.5.6.0 /usr/lib64/libKF5XmlGui.so.5.6.0 /usr/lib64/libQt5PrintSupport.so.5.4.0 /usr/lib64/libKF5TextWidgets.so.5.6.0 /usr/lib64/libKF5Service.so.5.6.0 /usr/lib64/libKF5Completion.so.5.6.0 /usr/lib64/libKF5IconThemes.so.5.6.0 /usr/lib64/libKF5ConfigWidgets.so.5.6.0 /usr/lib64/libKF5WidgetsAddons.so.5.6.0 /usr/lib64/libKF5GuiAddons.so.5.6.0 /usr/lib64/libKF5Codecs.so.5.6.0 /usr/lib64/libKF5ConfigGui.so.5.6.0 /usr/lib64/libQt5Xml.so.5.4.0 /usr/lib64/libKF5Auth.so.5.6.0 /usr/lib64/libKF5CoreAddons.so.5.6.0 /usr/lib64/libKF5I18n.so.5.6.0 /usr/lib64/libKF5SonnetUi.so.5.6.0 /usr/lib64/libKF5ItemViews.so.5.6.0 /usr/lib64/libQt5Network.so.5.4.0 /usr/lib64/libKF5ThreadWeaver.so.5.6.0 /usr/lib64/libKF5Wallet.so.5.6.0 /usr/lib64/libKF5ConfigCore.so.5.6.0 /usr/lib64/libKF5WindowSystem.so.5.6.0 /usr/lib64/libphonon4qt5.so.4.8.3 /usr/lib64/libQt5Widgets.so.5.4.0 /usr/lib64/libQt5Gui.so.5.4.0 /usr/lib64/libQt5DBus.so.5.4.0 /usr/lib64/libQt5Core.so.5.4.0 -lm -lz -lQt4::QtCore -Wl,-rpath,/var/tmp/portage/kde-apps/okular-5.9999/work/okular-5.9999_build: 
/usr/lib/gcc/x86_64-pc-linux-gnu/4.9.2/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lQt4::QtCore
collect2: error: ld returned 1 exit status
generators/ooo/CMakeFiles/okularGenerator_ooo.dir/build.make:261: recipe for target 'generators/ooo/okularGenerator_ooo.so' failed


Expected Results:  
should compile