- update to 3.1.1:
* The EGL back end now supports OpenGL applications, including
ANSYS Fluent, that use multiple X11 Display handles to render to
the same GLX drawable.
* The VirtualGL Faker now works around an issue whereby
applications using the GtkGLArea widget with GTK v3.15.2 through
v4.3.1 failed with "No available configurations for the given
[RGBA] pixel format" if GTK v3.15.2 through v4.3.1 had previously
been initialized on the 2D X server without VirtualGL.
* As required by the EGL spec, the interposed `eglSwapBuffers()`
function now flushes the current OpenGL context if the surface
being swapped is bound to that context. This fixes a flickering
issue that occurred with recent versions of Firefox.
* It is no longer necessary to enable the EGL back end in order to
use VirtualGL with 3D applications that use the EGL/X11 API. If
the GLX back end is enabled, then the EGL/X11 interposer will now
use the 3D X server.
* Fixed an issue in the VirtualGL Faker that caused random characters
and other elements of the Firefox browser window to disappear when
the window was resized.
* Fixed an issue in VirtualGL's `dlopen()` interposer
(**libdlfaker.so**) that interfered with the correct operation of
ANGLE (Almost Native Graphics Layer Engine.)
- add keyring for signature validation

* Now supports use of EGL as well as GLX
- Extend 64bit conditions to s390x ppc64 ppc64le aarch64