GL: remove the nv-egl-forward-compatible-context-unhappy workaround.

This was my bug, as requesting a forward-compatible context without
saying *what* version it should be forward compatible to makes no sense.
A followup to 73baab69ce.

doc/changelog.dox

@@ -420,11 +420,6 @@ See also:
     would assume a zero-sized framebuffer. This behavior is no longer silent
     but advertised as a @cpp "apitrace-zero-initial-viewport" @ce workaround.
     See @ref opengl-workarounds for more information.
--   Added a @cpp "nv-egl-forward-compatible-context-unhappy" @ce workaround
-    that removes @ref Platform::WindowlessEglApplication::Configuration::Flag::ForwardCompatible
-    from flags passed to `eglCreateContext()` as that otherwise causes NVidia
-    to fail with `EGL_BAD_MATCH`. See @ref opengl-workarounds for more
-    information.
 -   @ref GL::OpenGLTester no longer implicitly enables @ref GL::DebugOutput as
     it can be quite spammy when complex shaders or benchmarks are allowed. For
     easier debugging, users are encouraged to use the new

src/Magnum/GL/Implementation/driverSpecific.cpp

@@ -128,12 +128,6 @@ namespace {
    possible to get driver version through EGL, so enabling this unconditionally
    on all EGL NV contexts. */
 "nv-egl-incorrect-gl11-function-pointers",
-
-/* NVidia is unhappy when EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR is
-   present among attributes passed to eglCreateContext(), blowing up with
-   EGL_BAD_MATCH. This flag is enabled by default, wiping it away to make the
-   context creation work. */
-"nv-egl-forward-compatible-context-unhappy",
 #endif
 
 #ifndef MAGNUM_TARGET_GLES

src/Magnum/Platform/WindowlessEglApplication.cpp

@@ -226,16 +226,6 @@ WindowlessEglContext::WindowlessEglContext(const Configuration& configuration, G
         flags |= Configuration::Flag::Debug;
     #endif
 
-    #ifndef MAGNUM_TARGET_GLES
-    /* NVidia doesn't like EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR for
-       some reason, failing eglCreateContext() with EGL_BAD_MATCH. If this flag
-       is set, wipe it away. */
-    const char* vendor = eglQueryString(_display, EGL_VENDOR);
-    if((flags & Configuration::Flag::ForwardCompatible) && vendor && std::strcmp(vendor, "NVIDIA") == 0 && (!magnumContext || !magnumContext->isDriverWorkaroundDisabled("nv-egl-forward-compatible-context-unhappy"))) {
-        flags &= ~Configuration::Flag::ForwardCompatible;
-    }
-    #endif
-
     #if !defined(MAGNUM_TARGET_GLES) || defined(MAGNUM_TARGET_WEBGL)
     const /* Is modified below to work around a SwiftShader limitation */
     #endif