* target.c (update_current_target): Inherit to_log_command.

* target.c (update_current_target): Inherit to_log_command.
* target.h (struct target_ops). Add to_log_command.
(target_log_command): New macro.
* top.c (execute_command): Call target_log_command() rather than
serial_log_command().
* monitor.c (init_base_monitor_ops): Initialize to_log_command.
* remote-m32r-sdi.c (init_m32r_ops): Likewise.
* remote-mips.c (_initialize_remote_mips): Likewise.
* remote.c (init_remote_ops): Likewise.