virgl: Implement seamless cube maps

This was previously ignored.

Along with the virglrenderer patch, this fixes ~100 dEQP tests:
dEQP-GLES3.functional.texture.filtering.cube.*

Signed-off-by: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

src/gallium/drivers/virgl/virgl_encode.c

@@ -566,7 +566,8 @@ int virgl_encode_sampler_state(struct virgl_context *ctx,
       VIRGL_OBJ_SAMPLE_STATE_S0_MIN_MIP_FILTER(state->min_mip_filter) |
       VIRGL_OBJ_SAMPLE_STATE_S0_MAG_IMG_FILTER(state->mag_img_filter) |
       VIRGL_OBJ_SAMPLE_STATE_S0_COMPARE_MODE(state->compare_mode) |
-      VIRGL_OBJ_SAMPLE_STATE_S0_COMPARE_FUNC(state->compare_func);
+      VIRGL_OBJ_SAMPLE_STATE_S0_COMPARE_FUNC(state->compare_func) |
+      VIRGL_OBJ_SAMPLE_STATE_S0_SEAMLESS_CUBE_MAP(state->seamless_cube_map);
 
    virgl_encoder_write_dword(ctx->cbuf, tmp);
    virgl_encoder_write_dword(ctx->cbuf, fui(state->lod_bias));

src/gallium/drivers/virgl/virgl_protocol.h

@@ -330,6 +330,7 @@ enum virgl_context_cmd {
 #define VIRGL_OBJ_SAMPLE_STATE_S0_MAG_IMG_FILTER(x) (((x) & 0x3) << 13)
 #define VIRGL_OBJ_SAMPLE_STATE_S0_COMPARE_MODE(x) (((x) & 0x1) << 15)
 #define VIRGL_OBJ_SAMPLE_STATE_S0_COMPARE_FUNC(x) (((x) & 0x7) << 16)
+#define VIRGL_OBJ_SAMPLE_STATE_S0_SEAMLESS_CUBE_MAP(x) (((x) & 0x1) << 19)
 
 #define VIRGL_OBJ_SAMPLER_STATE_LOD_BIAS 3
 #define VIRGL_OBJ_SAMPLER_STATE_MIN_LOD 4