vout/opengl: fix flipped and transposed orientation
vout/opengl: fix flipped and transposed orientation

Now that GL_CULL_FACE is enabled (for 360 videos), it's not possible to flip or
transpose the video by touching the vertex positions. The orientation matrix
must now be applied on the textures coordinates.

Signed-off-by: Thomas Guillem <5f50a84c1fa3bcff146405017f36aec1a10a9e38@gllm.fr>

xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc,xkfz007/vlc