multimedia/vvenc: fix build on big-endian

ld: error: duplicate symbol: vvenc::byteReverse(unsigned int*, unsigned int)

defined at PicYuvMD5.cpp

source/Lib/vvenc/CMakeFiles/vvenc.dir/__/CommonLib/PicYuvMD5.cpp.o:(vvenc::byteReverse(unsigned int*, unsigned int))

defined at EncGOP.cpp

source/Lib/vvenc/CMakeFiles/vvenc.dir/__/EncoderLib/EncGOP.cpp.o:(.text+0x0)