* mi-cmd-stack.c (mi_cmd_stack_list_frames): Output a list of

* mi-cmd-stack.c (mi_cmd_stack_list_frames): Output a list of
"stack" entries.
(mi_cmd_stack_list_args): Ditto for "stack-args".
* gdbmi.texinfo (stack-list-frames, stack-list-arguments): Update
documentation.
(GDB/MI Stack Manipulation Commands): Fix section title.  Was
Stack Manipulation Commands in GDB/MI.
* mi-stack.exp: Update. Output for stack=..., args=... and
stack-args=... changed to a list.