ci: also build proprietary USB loader

The proprietary USB loader as provided by rkbin is useful for a variety
of tasks, such as wiping the factory image off eMMC with rockusb. Build
it, and ship it as part of the CI pipeline.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>

.gitlab-ci.yml

@@ -46,8 +46,10 @@ build armsom-sige5:
     - make sige5-rk3576_defconfig
     - make -j$(nproc)
 
-    # TODO: usb loader
+    # proprietary USB loader
+    - cd $CI_PROJECT_DIR/../rkbin && ./tools/boot_merger RKBOOT/RK3576MINIALL.ini && mv *spl_loader*.bin $CI_PROJECT_DIR
 
   artifacts:
     paths:
       - u-boot-rockchip.bin
+      - rk3576_spl_loader_*.bin