Previously, gl->DXOpenDeviceNV was called twice using dxva2 with dxinterop. AMD
drivers refused to allow this. With this commit, context_dxinterop sets its own
implementation of MPGetNativeDisplay, which can return either a
IDirect3DDevice9Ex or a dxinterop_device_HANDLE depending on the "name" request
string. hwdec_dxva2gldx then requests both of these avoiding the need to call
gl->DXOpenDeviceNV a second time.
* use mp_HRESULT_to_str/mp_LastError_to_str
* make some messages non-identical
* replace "GL" -> "OpenGL"
* change some MP_FATAL to MP_ERR that don't actually kill the vo
Do this to make the license situation less confusing.
This change should be of no consequence, since LGPL is compatible with
GPL anyway, and making it LGPL-only does not restrict the use with GPL
code.
Additionally, the wording implies that this is allowed, and that we can
just remove the GPL part.