8285890: Fix some @param tags

Reviewed-by: dfuchs, mullan, darcy, mchung, wetmore

src/java.base/share/classes/java/lang/ref/PhantomReference.java

@@ -45,7 +45,7 @@ import jdk.internal.vm.annotation.IntrinsicCandidate;
  * phantom reference always returns {@code null}.
  * The {@link #refersTo(Object) refersTo} method can be used to test
  * whether some object is the referent of a phantom reference.
- * @param<T> the type of the referent
+ * @param <T> the type of the referent
  *
  * @author   Mark Reinhold
  * @since    1.2

src/java.base/share/classes/java/lang/ref/Reference.java

@@ -36,7 +36,7 @@ import jdk.internal.ref.Cleaner;
  * operations common to all reference objects.  Because reference objects are
  * implemented in close cooperation with the garbage collector, this class may
  * not be subclassed directly.
- * @param<T> the type of the referent
+ * @param <T> the type of the referent
  *
  * @author   Mark Reinhold
  * @since    1.2

src/java.base/share/classes/java/lang/ref/ReferenceQueue.java

@@ -31,7 +31,7 @@ import jdk.internal.misc.VM;
 /**
  * Reference queues, to which registered reference objects are appended by the
  * garbage collector after the appropriate reachability changes are detected.
- * @param<T> the type of the reference object
+ * @param <T> the type of the reference object
  *
  * @author   Mark Reinhold
  * @since    1.2

src/java.base/share/classes/java/lang/ref/SoftReference.java

@@ -56,7 +56,7 @@ package java.lang.ref;
  * prevent its most recently used entries from being discarded by keeping
  * strong referents to those entries, leaving the remaining entries to be
  * discarded at the discretion of the garbage collector.
- * @param<T> the type of the referent
+ * @param <T> the type of the referent
  *
  * @author   Mark Reinhold
  * @since    1.2

src/java.base/share/classes/java/lang/ref/WeakReference.java

@@ -40,7 +40,7 @@ package java.lang.ref;
  * weakly-reachable objects to be finalizable.  At the same time or at some
  * later time it will enqueue those newly-cleared weak references that are
  * registered with reference queues.
- * @param<T> the type of the referent
+ * @param <T> the type of the referent
  *
  * @author   Mark Reinhold
  * @since    1.2