[binutils-gdb] Use std::vector in compile-loc2c.c

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 711799d513206f6d8fc3dbfa81dcdecdb2ce6ece ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 711799d513206f6d8fc3dbfa81dcdecdb2ce6ece

Use std::vector in compile-loc2c.c

This changes compile-loc2c.c to use std::vector in place of a VEC,
allowing the removal of a cleanup.

gdb/ChangeLog
2017-04-12  Tom Tromey  <tom@tromey.com>

	* compile/compile-loc2c.c (compute_stack_depth_worker): Change
	type of "to_do".  Update.
	(compute_stack_depth): Use std::vector.