[binutils-gdb] Allocate cmd_list_element with new

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT e2fc72e2c594968084b936bc5dc4702a2c0694f8 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: e2fc72e2c594968084b936bc5dc4702a2c0694f8

Allocate cmd_list_element with new

This adds a constructor and destructor to cmd_list_element and changes
it to be allocated with new.  This will be useful in a subsequent
patch.

ChangeLog
2018-05-04  Tom Tromey  <tom@tromey.com>

	* cli/cli-decode.h (cmd_list_element): New constructor.
	(~cmd_list_element): New destructor.
	(struct cmd_list_element): Add initializers.
	* cli/cli-decode.c (do_add_cmd): Use "new".
	(delete_cmd): Use "delete".