vdpau: do not export _vdp_DRI2* functions
vdpau: do not export _vdp_DRI2* functions

Neither one is part of the public API, thus should never be used outside
of the library itself.

Add macro PRIVATE, that is used to annotate the function visibility by
setting __attribute__((visibility("hidden"))).

v2: Provide only PRIVATE macro. Requested by Aaron.

Signed-off-by: Emil Velikov <4c996f2f093ddd0585a556460b4cc3ba555546ef@gmail.com>
Reviewed-by: Aaron Plattner <7c39395e2e801146cdbd7fb4a41282e4f38db44e@nvidia.com>
Signed-off-by: Aaron Plattner <7c39395e2e801146cdbd7fb4a41282e4f38db44e@nvidia.com>

mosterta/libvdpau,mosterta/libvdpau,Distrotech/libvdpau,Distrotech/libvdpau,Distrotech/libvdpau,mosterta/libvdpau