Improve javadoc for all addons (#15667)

Signed-off-by: Holger Friedrich <mail@holger-friedrich.de>

bundles/org.openhab.binding.pixometer/src/main/java/org/openhab/binding/pixometer/internal/data/MeterState.java

@@ -32,8 +32,7 @@ public class MeterState {
     /**
      * Initialize times from the given timestamps
      *
-     * @param lastReadingDate time of last reading as ZonedDateTime
-     * @param lastRefreshTime time of last refresh as ZonedDateTime
+     * @param reading last reading
      */
     public MeterState(ReadingInstance reading) {
         this.readingValue = reading.getValue();