In some configuration, xmon help string is larger than xmon_printf
buffer.  We need not to use printf.  This patch adds xmon_puts and
change to use it to show help string.
Signed-off-by: NKou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: NPaul Mackerras <paulus@samba.org>