openharmony-linux-demo-dashboard.conf: Use a loading logo for weston wallpaper

This would make the boot process into the browser a bit clearer as
having Home Assistant up and running takes a couple of good seconds.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-ohos-demo/conf/distro/openharmony-linux-demo-dashboard.conf

@@ -30,6 +30,6 @@ EPIPHANY_URL = "http://localhost:8123"
 EPIPHANY_RDEPENDS = "python3-homeassistant"
 EPIPHANY_SERVICE_ENABLED = "1"
 
-WESTON_INI_BACKGROUND_IMAGE = "/usr/share/backgrounds/ostc-logo-small.png"
+WESTON_INI_BACKGROUND_IMAGE = "/usr/share/backgrounds/ostc-logo-small-loading.png"
 WESTON_INI_BACKGROUND_COLOR = "0xffffffff"
 WESTON_INI_BACKGROUND_TYPE = "centered"