Update the headers to a more recent version while it brings no improvements at this moment, it can in the future.
Update glcorearb.h from 7 February 2019
Update wglext.h from 33248 (10-24-2016) to 20200813 (13 August 2020)
Update glext.h from 33248 (10-24-2016) to 20210420 ( 20 April 2021)
Creation of khrplatform.h
* some preliminary work to test/benchmark bindless texture in the future (glsl was not yet updated)
Bindless texture allow to get a GPU texture pointer and then set it directly
to the shader as a basic uniform.
=> no more texture unit selection/validation
=> no more texture validation neither texture hash lookup
3rdparty: update gl header to the latest gl4.4
git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5720 96395faa-99c1-11dd-bbfe-3dabce05a288