webkit-efl: add dependency on gstreamer
* fails without it:
| -- checking for module 'gstreamer-0.10'
| -- package 'gstreamer-0.10' not found
| -- checking for module 'gstreamer-base-0.10'
| -- package 'gstreamer-base-0.10' not found
| -- checking for module 'gstreamer-app-0.10'
| -- package 'gstreamer-app-0.10' not found
| -- checking for module 'gstreamer-audio-0.10'
| -- package 'gstreamer-audio-0.10' not found
| -- checking for module 'gstreamer-fft-0.10'
| -- package 'gstreamer-fft-0.10' not found
| -- checking for module 'gstreamer-interfaces-0.10'
| -- package 'gstreamer-interfaces-0.10' not found
| -- checking for module 'gstreamer-pbutils-0.10'
| -- package 'gstreamer-pbutils-0.10' not found
| -- checking for module 'gstreamer-video-0.10'
| -- package 'gstreamer-video-0.10' not found
| CMake Error at cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:108 (message):
| Could NOT find GStreamer (missing: GSTREAMER_INCLUDE_DIRS
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>