mesalib: Enable Vulkan drivers

Description of Vulkan API [1]:

> Vulkan is a low-overhead, cross-platform 3D graphics and compute API.
> Vulkan targets high-performance realtime 3D graphics applications such
> as video games and interactive media across all platforms. Compared
> with OpenGL and Direct3D 11 and like Direct3D 12 and Mantle, Vulkan is
> intended to offer higher performance and more balanced CPU/GPU usage.
> Other major differences from Direct3D 11 (and prior) and OpenGL are
> Vulkan being a considerably lower level API and offering parallel
> tasking. Vulkan also has the ability to render 2D graphics
> applications, however it is generally suited for 3D. In addition to
> its lower CPU usage, Vulkan is also able to better distribute work
> amongst multiple CPU cores.

[1] https://en.wikipedia.org/wiki/Vulkan_(API)

mesalib.be0

@@ -63,7 +63,8 @@ mee_configure() {
         --enable-glx-tls \
         --with-llvm-shared-libs \
         --with-egl-platforms="drm,x11" \
-        --with-gallium-drivers="nouveau,r600,radeonsi,svga,swrast"
+        --with-gallium-drivers="nouveau,r600,radeonsi,svga,swrast" \
+        --with-vulkan-drivers="intel,radeon"
 }
 
 #mee_build() {