[iostream.cons] Add std:: qualified for move

Author: hewillk

source/iostreams.tex

@@ -5819,7 +5819,7 @@
 \effects
 Move constructs from the rvalue \tcode{rhs} by
 constructing the \tcode{basic_istream} base class with
-\tcode{move(rhs)}.
+\tcode{std::move(rhs)}.
 \end{itemdescr}
 
 \rSec4[iostream.dest]{Destructor}