[miio] Fix double stratus update (#9901)

closing: #9898

Signed-off-by: Marcel Verpaalen <marcel@verpaalen.com>

bundles/org.openhab.binding.miio/src/main/java/org/openhab/binding/miio/internal/handler/MiIoBasicHandler.java

@@ -595,6 +595,7 @@ public class MiIoBasicHandler extends MiIoAbstractHandler {
                 logger.debug("'{}' channel '{}' has unit '{}' with symbol '{}'.", getThing().getUID(),
                         basicChannel.getChannel(), basicChannel.getUnit(), unit);
                 updateState(basicChannel.getChannel(), new QuantityType<>(val.getAsBigDecimal(), unit));
+                return;
             } else {
                 logger.debug("Unit '{}' used by '{}' channel '{}' is not found.. using default unit.",
                         getThing().getUID(), basicChannel.getUnit(), basicChannel.getChannel());