Kodi Direct3D 11 & DXVA updates 4.0.2

Updated at 14-07-2020 (forked from Kodi 19 alpha master).

Changes in 4.0.2:

• Removed ALLOW_TEARING flag.
• Use multi-threading protection only when necessary (cause a little overload).
• Updated with latest master branch commits.

All changes:

• Updated include headers to D3D 11.4 API and DX feature level 12_1.
• Removed advancedsettings options "disableDXVAdiscretedecoder" and "allowdiscretedecoder".
• Improved detection of NV12 shared textures capability using more up to date D3D11_FEATURE_DATA_D3D11_OPTIONS4.
• Improved calculation of number buffers need for DXVA HEVC decoding.
• Improved textures copy function with safe "wait to completed operation" (NVIDIA stuttering fix).
• Improved Kodi logging with graphics card model and DX feature level used without need activate debug mode.
• Use multi-threading protection only when necessary (cause a little overload).