gdb: move set remote commands to remote.c

gdb: move set remote commands to remote.c

Commands "set debug remote" and "set remotetimeout" are defined in
cli/cli-cmds.c, I think it would make more sense for them to be in
remote.c.

gdb/ChangeLog:

	* cli/cli-cmds.c (show_remote_debug): Remove.
	(show_remote_timeout): Remove.
	(_initialize_cli_cmds): Don't register commands.
	* remote.c (show_remote_debug): Move here.
	(show_remote_timeout): Move here.
	(_initialize_remote): Register commands.

Change-Id: Ic4d81888aa4f8dde89d1d29397ef19a08951b80b