Need to specify -DUSE_OPENGLES=1 to build manually on arm

[Gerry Boland]

Need to specify -DUSE_OPENGLES=1 to build manually on arm.

Otherwise:
mirbuffersgtexture.cpp.o: In function `MirBufferSGTexture::~MirBufferSGTexture()':
/home/phablet/src/noloop/src/modules/Unity/Application/mirbuffersgtexture.cpp:44: undefined reference to `glDeleteTextures'
CMakeFiles/unityapplicationplugin.dir/mirbuffersgtexture.cpp.o: In function `MirBufferSGTexture::bind()':
/home/phablet/src/noloop/src/modules/Unity/Application/mirbuffersgtexture.cpp:79: undefined reference to `glBindTexture'
...

Look into an autodetect option if possible