cmake: Change CMAKE_SOURCE_DIR to OPAE_SDK_SOURCE
Change samples/CMakeLists.txt to use ${OPAE_SDK_SOURCE} in its include
path instead of ${CMAKE_SOURCE_DIR}. This allows it to build when the
OPAE repo is a subdirectory of another CMake based build.
## POSSIBILITY OF SUCH DAMAGE.
include_directories(${OPAE_INCLUDE_DIR}
- ${CMAKE_SOURCE_DIR}/libopae/src )
+ ${OPAE_SDK_SOURCE}/libopae/src )
set(CMAKE_C_FLAGS "-std=gnu99 ${CMAKE_C_FLAGS}")
