8303083: (bf) Remove private DirectByteBuffer(long, int) constructor before JDK 21 GA

Reviewed-by: alanb, lancea

src/java.base/share/classes/java/nio/Direct-X-Buffer.java.template

@@ -187,11 +187,6 @@ class Direct$Type$Buffer$RW$$BO$
         att = null;
     }
 
-    // Temporarily keep the long,int constructor around
-    private Direct$Type$Buffer(long addr, int cap) {
-        this(addr, (long)cap);
-    }
-
     // Throw an IllegalArgumentException if the capacity is not in
     // the range [0, Integer.MAX_VALUE]
     //