vrend: add a cap for astc compressed 3d-textures

This is useful for knowing if we can expose
KHR_texture_compression_astc_sliced_3d in the guest.

Signed-off-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>

src/virgl_hw.h

@@ -245,6 +245,7 @@ enum virgl_formats {
 #define VIRGL_CAP_MULTI_DRAW_INDIRECT  (1 << 21)
 #define VIRGL_CAP_INDIRECT_PARAMS      (1 << 22)
 #define VIRGL_CAP_TRANSFORM_FEEDBACK3  (1 << 23)
+#define VIRGL_CAP_3D_ASTC              (1 << 24)
 
 /* virgl bind flags - these are compatible with mesa 10.5 gallium.
  * but are fixed, no other should be passed to virgl either.

src/vrend_renderer.c

@@ -8791,6 +8791,9 @@ static void vrend_renderer_fill_caps_v2(int gl_ver, int gles_ver,  union virgl_c
             set_format_bit(&caps->v2.supported_readback_formats, VIRGL_FORMAT_R32G32B32A32_FLOAT);
       }
    }
+
+   if (epoxy_has_gl_extension("GL_KHR_texture_compression_astc_sliced_3d"))
+      caps->v2.capability_bits |= VIRGL_CAP_3D_ASTC;
 }
 
 void vrend_renderer_fill_caps(uint32_t set, UNUSED uint32_t version,