dri/kopper: Add translations for sRGB formats

There was DRI_IMAGE_FORMAT -> FourCC format translation, but this was
unreachable as we only ever called image_format_to_fourcc() on the
result of get_dri_format().

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27709>

src/gallium/frontends/dri/kopper.c

@@ -186,6 +186,15 @@ get_dri_format(enum pipe_format pf)
 {
    int image_format;
    switch (pf) {
+   case PIPE_FORMAT_BGRA8888_SRGB:
+      image_format = __DRI_IMAGE_FORMAT_SARGB8;
+      break;
+   case PIPE_FORMAT_BGRX8888_SRGB:
+      image_format = __DRI_IMAGE_FORMAT_SXRGB8;
+      break;
+   case PIPE_FORMAT_RGBA8888_SRGB:
+      image_format = __DRI_IMAGE_FORMAT_SABGR8;
+      break;
    case PIPE_FORMAT_R16G16B16A16_FLOAT:
       image_format = __DRI_IMAGE_FORMAT_ABGR16161616F;
       break;