Add command completion for info variables, functions, args, and
locals. This completer only completes the command line options as
these commands all take a regexp which GDB can't really offer
completions for.
gdb/ChangeLog:
* cli/cli-utils.c (info_print_command_completer): New function.
* cli/cli-utils.h: Add 'completer.h' include, and forward
declaration for 'struct cmd_list_element'.
(info_print_command_completer): Declare.
* stack.c (_initialize_stack): Add completer for 'info locals' and
'info args'.
* symtab.c (_initialize_symtab): Add completer for 'info
variables' and 'info functions'.
* NEWS: Mention completion for additional info commands.
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