Adapts definitions preparing for #2632

Author: JJ

doc/Type/IO/Handle.pod6

@@ -353,8 +353,9 @@ with 'foo'.IO {
 
 Defined as:
 
-    sub lines(IO::Handle:D $fh = $*ARGFILES, $limit = Inf, :$close --> Seq:D)
-    method lines(IO::Handle:D:               $limit = Inf, :$close --> Seq:D)
+    sub    lines( $what = $*ARGFILES, |c)
+    method lines( IO::Handle:D: $limit, :$close )
+    method lines( IO::Handle:D:         :$close )
 
 Return a L<Seq|/type/Seq> each element of which is a line from the handle (that is
 chunks delineated by L«C<.nl-in>|/type/IO::Handle#method_nl-in»). If the