[binutils-gdb/gdb-8.0-branch] Replace "return" with "break"

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT d05228c1bb3b8f8b9e187c4b76d0c71a72ba15e8 ***

Author: Tom Tromey <tom@tromey.com>
Branch: gdb-8.0-branch
Commit: d05228c1bb3b8f8b9e187c4b76d0c71a72ba15e8

Replace "return" with "break"

This replaces a "return" with a "break" in rust_print_subexp, for
consistency.

2017-05-12  Tom Tromey  <tom@tromey.com>

	* rust-lang.c (rust_print_subexp): Replace "return" with "break".