Fix some Javadoc links

src/main/java/org/apache/commons/csv/ExtendedBufferedReader.java

@@ -84,7 +84,7 @@ long getCurrentLineNumber() {
      * Returns the last character that was read as an integer (0 to 65535). This will be the last character returned by
      * any of the read methods. This will not include a character read using the {@link #lookAhead()} method. If no
      * character has been read then this will return {@link Constants#UNDEFINED}. If the end of the stream was reached
-     * on the last read then this will return {@link Constants#EOF}.
+     * on the last read then this will return {@link org.apache.commons.io.IOUtils#EOF IOUtils#EOF}.
      *
      * @return the last character that was read
      */

src/main/java/org/apache/commons/csv/Lexer.java

@@ -467,7 +467,7 @@ boolean readEndOfLine(int ch) throws IOException {
      * On return, the next character is available by calling {@link ExtendedBufferedReader#getLastChar()}
      * on the input stream.
      *
-     * @return the unescaped character (as an int) or {@link Constants#EOF} if char following the escape is
+     * @return the unescaped character (as an int) or {@link org.apache.commons.io.IOUtils#EOF IOUtils#EOF} if char following the escape is
      *      invalid.
      * @throws IOException if there is a problem reading the stream or the end of stream is detected:
      *      the escape character is not allowed at end of stream