CMakeLists.txt: Hint to libmraa/mraajava
CMakeLists.txt: Hint to libmraa/mraajava

Small change - updated from PATHS to HINTS.  Search HINTS paths first to
provide location for mraa libraries.

Signed-off-by: Noel Eck <1e36ab6ededef40f3f16bdbc1b09eee72c5d08cf@intel.com>

stefan-andritoiu/upm,pylbert/upm,g-vidal/upm,malikabhi05/upm,g-vidal/upm,stefan-andritoiu/upm,Propanu/upm,g-vidal/upm,Jon-ICS/upm,jontrulson/upm,pylbert/upm,malikabhi05/upm,sasmita/upm,pylbert/upm,stefan-andritoiu/upm,skiselev/upm,skiselev/upm,skiselev/upm,malikabhi05/upm,Propanu/upm,malikabhi05/upm,jontrulson/upm,sasmita/upm,pylbert/upm,intel-iot-devkit/upm,intel-iot-devkit/upm,stefan-andritoiu/upm,skiselev/upm,pylbert/upm,jontrulson/upm,intel-iot-devkit/upm,Propanu/upm,intel-iot-devkit/upm,Propanu/upm,g-vidal/upm,sasmita/upm,Jon-ICS/upm,sasmita/upm,intel-iot-devkit/upm,stefan-andritoiu/upm,Jon-ICS/upm,Jon-ICS/upm,skiselev/upm,g-vidal/upm,Propanu/upm,intel-iot-devkit/upm,sasmita/upm,jontrulson/upm,jontrulson/upm,pylbert/upm,Propanu/upm,stefan-andritoiu/upm,Jon-ICS/upm,g-vidal/upm,malikabhi05/upm,skiselev/upm,malikabhi05/upm