qtwebkit: remove examples packages

* fixes:
  NOTE: multiple providers are available for runtime qtwebkit-examples (qtwebkit-examples, qtwebkit)
  NOTE: consider defining a PREFERRED_PROVIDER entry to match qtwebkit-examples
  NOTE: multiple providers are available for runtime qtwebkit-examples-dev (qtwebkit, qtwebkit-examples)
  NOTE: consider defining a PREFERRED_PROVIDER entry to match qtwebkit-examples-dev

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
cmake: disable test for Qt5Core

| CMake Error at tmp-eglibc/sysroots/qemuarm/usr/lib/cmake/Qt5Core/Qt5CoreConfig.cmake:27 (message):
|   The imported target "Qt5::Core" references the file
|
|      "/qmake"
|
|   but this file does not exist.  Possible reasons include:
|
|   * The file was deleted, renamed, or moved to another location.
|
|   * An install or uninstall procedure did not complete successfully.
|
|   * The installation package was faulty and contained
|
|      "tmp-eglibc/sysroots/qemuarm/usr/lib/cmake/Qt5Core/Qt5CoreConfigExtras.cmake"
|
|   but not all the files it references.
|
| Call Stack (most recent call first):
|   tmp-eglibc/sysroots/qemuarm/usr/lib/cmake/Qt5Core/Qt5CoreConfigExtras.cmake:6 (_qt5_Core_check_file_exists)
|   tmp-eglibc/sysroots/qemuarm/usr/lib/cmake/Qt5Core/Qt5CoreConfig.cmake:130 (include)
|   Tests/RunCMake/CMakeLists.txt:80 (find_package)

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>