[binutils-gdb] Use std::move in a few places

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 2f5404b3581d125a96f14d92c4a7985e8156d1d6 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 2f5404b3581d125a96f14d92c4a7985e8156d1d6

Use std::move in a few places

This patch adds std::move to few spots where it seems to be missing.

Regression tested by the buildbot.

ChangeLog
2017-08-14  Tom Tromey  <tom@tromey.com>

	* break-catch-throw.c (handle_gnu_v3_exceptions): Use std::move.
	* break-catch-syscall.c (create_syscall_event_catchpoint): Use
	std::move.
	* break-catch-sig.c (create_signal_catchpoint): Use std::move.